COPULATION, AND INSEMINATION OF THE FEMALE Preliminary to copulation the male grasshopper places himself well

forward onthebackof thefemale.

With

his forelegshe clasps the

pronotum

of the female, theclaws holdingatthenotchinthe anterior marginof theprothorax betweenthe

pronotum

andthesmallexposed part of the episternum; the intermediate legs clasp the middle of the female's body; the hind legs are held in various positions and takelittle part in thecopulatory act.

The

male then lowers his ab-

domen

along the side of the female's

abdomen

(in pictures almost invariablyonthe left side,butBoldyrevsays,sometimes onthe left,

sometimes onthe right).

The

genital lobe of the ninth segment of themaleis

now

depressedandthephallicorgansprotruded, the dorsal lobe of theaedeagusbeingturned

upward

and forward. In orderto exposethespermathecalaperture of the female,whichreceives theend of themale organ in copulation, the male, as describedby Boldyrev (1929) forLocustamigratoria, depresses the subgenital plateof the female with the anteriorhooks of the epiphallus.

The

penis is then introduced into thegenital

chamber

between and beneaththe ventral valves of the ovipositor and is inserted into the spermathecal canal.

InLocusta miffratoria, accordingto Boldyrev, the separation of the lowervalves of the ovipositorbytheorganof themale stretches the dorsal wall of the genital

chamber

and pulls back the folds that ordinarily conceal thespermathecal opening;thelatteris

now

^"opened wideandthepenisisplungedintoitright

up

toitsbase."

The

^penis,

or dorsal lobe of the aedeagus, inLocustamigratoriais long,slender, and tapering (fig. 32

B);

in forms in which the terminal part is

shortand thick,asin Melanophis (figs. 37, 38, 40), ^it seemshardly possible that theentire organ canbe inserted;probablyin suchcases only theapicalprocesses enter thespermathecalorifice.

During

copu- lationthecerciof themalearesaid tograspthebase of the subgenital

^2

SMITHSONIAN MISCELLANEOUS

COLLECTIONS \"0L. 94 plate of the female, while the distal part of the j^late is held

down

bythe epiphallus.

Paired grasshoppers remainthus together for a

number

of hours, or for a day or more, in

some

cases for

more

than

two

days, the duration of copulation apparently beingdetermined bythe length of time necessary for the formationof the spermatophore,orspermato- phores,

and

the transference of the latter to the female, or by the

number

of spermatophores produced. Individuals of each sex

may

have several successive matings.

Itis

now

well established for theAcrididaethatduring copulation the spermatozoaaretransferred

from

the maleto the femaleintrue spermatophores, which, as defined by

Cholodkowsky

(1910), are sperm-containingcapsules foniicdinthegenitalpassage of the male.

In

some

cases onlyasinglespermatophoreisproducedateach mating, which, with one end remaining in the genital passage of the male andthe other inserted well into thespermathecal duct of the female, forms a conduit

from

oneindividual tothe other through whichthe sperm are dischargedbythe action of the endophallic apparatus of the male; inother cases a

number

of small spermatophores are in- jected into the female.

The

spermatozoa, as in Tettigoniidae and Gryllidae, are united by their head ends in bundles, or spermato- desmata.

The

spermatophores of Locusta migratoria and their formation have been studied by

Iwanowa

(1926),

Sokolow

(1926), and Bol- dyrev (1929). Itappears that normally only one spermatophore is

producedbythisspeciesatasinglemating.

Iwanowa

reports finding sometimes three or four spermatophores in the receptaculum of the female, butBoldyrevgivesevidence that inseminationisaccomplished properly with one spermatophore, and that if the male attempts to insertasecondintothespermathecalorificetheprocess isnot natural and cannotresult inthedischarge of the spermatozoa.

A

spermatophore of Locustamigratoria, as described and figured by Boldyrev (fig. 32

D),

is an elongate structure with transparent walls, consisting of a proximal sacconstricted into two bladderlike compartments, and ofa long slender distal tube.

The

length of the entirespermatophoreis usually25^to27

mm,

butit

may

reach 29or 30

mm. The

spermatophore thus greatly exceeds the length of the intromittent organ (fig. 32 B), since the latter measures not

more

than ₅or 6

mm from

the gonoporeat thebottom of the spermato- phoresacof the endophallus {sps) tothetips of theapicalprocesses of the aedeagus.

Only

thedistal tubular part of the spermatophore

is introducedintothe spermathecalcanal.

The

extrusion of thetube,

NO. 6

GRASSHOPPER ABDOMEN

SNODGRASS _"J^

Boldyrev says, requires an hour or more, and the discharge of the

sperm

is not completed until 5| to i8hoursafter copulation begins, thetimeapparentlybeingdependentonthetemperature.

On

opening thegenital organsof maleskilledduring copulation, Boldyrev found that thefirstbladder of the spermatophore is held intheejaculatory sac (fig. 32B, e']s), while thesecondliesin the

membranous

part of theendophallic cavityheretermedthe spermatophoresac (sps).

The

long spermatophore tube extends through the phallotreme cleft and protrudes forward

from

the distal end of the aedeagusbetween the bases of the anteriorapical processes (C);in copulationit isdeeply inserted into the spermathecal duct.

During

mating the

two

sexes are thus united by a tubular conduit through which the

sperm

are drivenbythe action of the endophallicapparatus

from

themale into the female.

At

the end of copulation the spermatophore tube is not

drawn

out of the female, butisbrokenofifnearitsbase.

The

detached tubeisretained a long time inthespermathecalcanal;the basal part of the spermatophore is soon rejected

from

the male.

With Anacridium

aegyptium, as

shown

by

Fedorov

(1927), in- semination of thefemaleisaccomplished bythe introduction of

from

6to30 spermatophores^intothespermatheca,theusual

number

being

from

12 to 18. In this species, however, the spermatophores are of relatively smallsize,about i

mm

inlength.

Each

capsule isa hyaline body,broaderattheanterior end,which. bears a smallappendageeasily broken off.

The

spermatophores are formed in the beginning of the ejaculatory duct, but theydonotattain their final shapeuntilthey reach the terminal part of the aedeagus.

Fedorov

believes that the spermatophores are all prepared during copulation, and that this accounts for the length of the copulatory period

—

1| or 2 hours being necessary for thecompletionofonecapsule

and

itstransference tothe female.

He

findsthus that

6

to 12spermatophores correspond with 18 to 24 hours of copulation, 18to 24 with 36 hours, and 30 with60hours. Inabout

4

to6 hoursafter thebeginning of copula- tion,

Fedorov

says,a milky-whitejellylike

mass

containing the

empty

spermatophoresthathave been ejected

from

the spermathecacollects betweenthe lowervalves of the ovipositor

where

it becomes brittle andyellow as itdries, and aftera

few

hours is lost, leavingno evi- dence of the insemination that has taken place.

EXAMPLES

OF

THE MALE

GENITALIA OF ACRIDIDAE

The

following descriptions of the malegenitaliaof representative species of the several acridid subfamilies will serve to illustrate the nature ofspecificvariations inthe

form

of theorgans,and will

show

the fundamental unity of structure throughout the family.

74

SMITHSONIAN MISCELLANEOUS

COLLECTIONS VOL. 94 ChorthippusbicolorCharp.

— The

Acridinae (Tryxalinae) have the typical acridid structure of the male genital organs, except that the distalpart of the dorsal lobe of theaedeagus is suppressed, and the apicalprocesses,which havethe

form

of fourlong, closelyappressed prongs,arise directly

from

the proximalpart (figs.28E,29 C).

The

structure of the male genital organs of Chorthippus bicolor is

shown

infigure28.

The

aedeagus (E,

Aed)

includes a dorsal lobe (dl) and a ventral lobe (vl), but theformer consists principally of the usualproximalpart of the dorsal lobe (m), whichbearsdirectly

-Malegenitalia of Chorthippus bicolor (Acridinae).

A, endofabdomen. B, dorsal lobeofaedeagusandlateralapodeme,leftside.

C, aedeagal apodemes, dorsal view. D.epiphallus, dorsalview. E,phallic or- gans and floor of genital chamber, lateral view. F, endophallus and distal partofaedeagus.

thefour large apicalprocessesabove noted (B, n,p).

The

aedeagal

apodemes

are welldevelopedas long tapering

arms

extending forward

from

the base of theaedeagus (B,

Apa)

in deep invaginations be- neath the basal fold

(E)

;theirproximalpartsareunitedbya strong

zygoma

(C, s) intheundersurface of the basal fold (B).

From

each of the apical processes of theaedeagus (F, n, p) ^{a. sclerite} extends proximallyinthe inner wall of the endophallicmeatus (o, q).

Here

the extremities of the dorsal pair of sclerites are united by a wide dorsalbridge (t)^,while the taperingendsofthe ventralscleritesare sharply bent

upward

(s) and then graduallyexpanded anteriorlyto

NO. 6

GRASSHOPPER ABDOMEN

SNODGRASS 75

form

the largelateralplates (u) of the endophalicwalls.

The

ejacu- latory sac (ejs) opens ventrally into the spermatophore sac of the endophallus (sps) betweenthe gonoporeprocesses (y) of the^lateral plates,andthespermatophoresacdischargesthroughthewide meatus and the phallotreme.

The

epiphallus is a large sclerite of the usual type of structure (fig.28

D)

seated onthe floorof the genital

chamber

(E,

Epph)

at the anteriorendof the surface that formsthe fold {hf) overlapping thebase of the aedeagus.

IXSL

Malegenitalia ofMcrmiria maculipcnnis (Acridinae).

A, endofabdomen. B,epiphallus. C,phallic organs with floor ofgenital chamber and muscles of endophallic bulb. D, endophallus and distal part of aedeagus. E, regulator mechanism of the gonopore, ventral view, closed. F, same,gonoporeopen.

Mermiria

macidipennis Bruner.

— ^The

only differences in themale genitaliabetweenthisspecies andthelastare in details of

form

and relative sizeof the parts (fig.29).

The

epiphallus (B, C,

Epph)

has the usualshape;the basal fold (C, hf) formsa large hoodlike cover- ingover the base of the aedeagus.

The

four large apical processes ofthe aedeagus,inthe retracted condition,project dorsally

from

the supporting proximal part

{m)

of the dorsal lobe; the ventral lobe {vl) projects like a trough beneath the latter.

The

endophallus is large (D), but its lateral plates {11) with their

apodemes (w)

and gonoporeprocesses (y) are of^typicalform.

The

closingand opening

mechanism

of thegonopore is easily studied in this species (E, F).

1^

SMITHSONIAN MISCELLANEOUS

COLLECTIONS VOL. 94

Camiuda

pcllucida (Scudder).

—

There is little inthe structure of themalegenitaliatodistinguishthisoedipodine species (figs.30,31)

from

the acridine species just described, though there are

many

differences to benoted in details of

form

and relative sizes of the

A ^ B

Fig. 30.

—

End of themale abdomenof Camnulapellucida (Oedipodinae).

A, lateral view. B, dorsal view.

Dej _ejs

y

Fig. 31.

—

Male genitalia of Camnula pellucida (Oedipodinae).

A, the phallic organs situated on floorof genital chamber, and muscles of endophallic bulb. B,epiphallus, dorsalview, andassociated retractor muscles.

C, dorsal lobeof aedeagusand lateralapodeme, leftside. D, endophallus and apical processesofaedeagus.

parts.

The

epiphallus is large and strongly developed (fig. 31A, Epph, B).

The

basal fold (A, _hf) covers the base of theaedeagus in the usualmanner.

The

dorsal lobe of the aedeagus consists of a small proximal part (C, ni) bearing two strong apodemal arms (Apa), and of fourlongcurvedapical processes (11, p).

The

^ventral

NO. 6

GRASSHOPPER ABDOMEN —

^SNODGRASS 17 lobe(A,vl) isunusually largeandensheaths

much

of the dorsallobe.

The

endophallus has thetypical

form

(D,

Enph),

withwell-developed apodemes (ze^) and gonoporeprocesses (y).

Locusfa migratoria L.

— The

aedeagus of Locusta migratoria is quite different inshape

from

that of theother species here described, butitspeculiarities

may

be seen asanexaggeration of the structurein Camnula.

The

ventral lobeisverylargeand,inthe retracted position

Fig. ^2.

—

Male genitalia of Locusta migratoria (Oedipodinae), and acridid spermatophores.

A,phallicorgansonfloor ofgenitalchamber,with endophallusandejaculatory sacbeneaththelatter. B, dorsal lobeofaedeagus, with aedeagalapodemes and endophallus exposed by removal of floor of genital chamber and ventral lobe ofaedeagus. C,aedeagusinprotractedposition,with protrudingspermatophore (Sphr). D, spermatophore of Locustamigratoria. E,spermatophoreof Cal- liptamusifalicus. (C, D,

E

fromBoldyrev, 1929.)

of the phallic organs (fig. 32

A),

completely conceals all but the terminal parts of the dorsal lobe. Its upturned lateral walls contain each a largequadrateplate (vl) lyingin avertical plane atthe side of the base of the dorsal lobe;ventrallythe

two

platesare unitedby a median

membranous

area of the lobe.

When

the ventral lobe is

removed

(B) the dorsal lobe of theaedeagus (dl) isseentohavethe

form

of along, tapering tube,curved

upward

and ending in four slenderapical processes.

The

organ, however,isnotliterallytubular, sincetheposterior wall is deeplycleft to its base: theopeningis the

78

SMITHSONIAN MISCELLANEOUS

COLLECTIONS VOL. 94