40 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL, 96 The seminal vesicles.- — ^The presence of special vesicles for the

storage of the spermatozoa appears tohave been overlooked

by

^other students of the reproductive organs of the roaches. Ito (1924) ^states there are

no

seminal vesicles in Blattaoricntalis,

and

that the

sperm

is stored in the anterior enlarged part of the ejaculatory duct. Miall

and Denny,

as above noted, believed that the accessory gland tubules

Eppt

XT

rPhm

Fig. 12.

—

Blattoidea: adultand immature structure of the male abdomen, and nymphal genitalia of Blatta oricntalis Linnaeus.

A, endofabdomenof adultmale,dorsal view. B,same,ventralview.C,same, posterior view. D, nymph 11

mm

long, ventral surface of abdomen. E, same, genital chamber exposed from above, showing three simple phallomeres aris- ing from anterior wall around gonopore. F, nymph 22

mm

^{long, showing}

later stage of phallomeres, and mesodermal ampullae united with anterior end ofectodermal ejaculatoryduct.

Amp,

mesodermal ampulla of ejaculatory duct; Cer, cercus; Dej, ductus ejaculatorius; Eppt. epiproct; GC, genital chamber; IPInn, left phallomere

;

Papt, paraproct; rPhm,right phallomere; Sty, stylus; Vd,vas deferens; vPhni, ventral phallomere; x-x, cut wall of genital chamber.

are filled with spermatozoa. How^ever, in Blatta, Periplancta,

and

Blattella, at least, there are special sperm-containing vesicles arising

from

the anteriorendof the ejaculatory duct

among

theglandtubules.

The

seminal vesicles of Blattellaare tw^o small oval sacs arising close together

from

the end of the right branch of the ejaculatory duct (fig. 16C,

Vsm), where

ordinarilythey are concealed

by

the accessory glandtubules.

They

are filledwith spermatozoa,

and

are similartothe

sperm

vesicles of the mantid

Tenodera

(fig.

9B)

except that both

NO. 5

MALE GENITALIA

OF

ORTHOPTEROID

INSECTS

SNODGRASS

4I are dextralin position. InBlatta

and

Periplanetathe seminalvesicles consist of

two

groups of small pyriform sacs, six or seven on each side, arising

from

the ventral surface of the ejaculatory duct at the base of the area of the small

median

gland tubules (fig. 15 E, Vsiii).

The

vesicles are distinguishable

from

the smaller glands by their slightlylarger size

and more opaque

whiteness; theyare clearly

shown

inBlattahy Miall

and Denny

(1886, fig.99, ^i),

who

didnot recognize their function.

The

sacs are filled with spermatozoa,

which must

be stored in

them

by the time the testes go into a state of degeneration.

The

spermatozoa of Blattidae are very small as

compared

with those of Mantidae,

and

are not attached to one another in bundles.

TJie pJiallic gland.

— A

^largegland of

unknown

function, the ^"con- globate gland ^" of Miall

and Denny,

or ^" prostate gland^" of

some

other writers, is associated with the external genital organs of

male

Blattidae. It lies beneath the accessory glands

and

ejaculatory duct,

and

opens

on

the phallic region.

The

phallicgland of Blatta orientalis is

an

elongate sac (fig. ii C,

PhGld)

tapering posteriorlyinto thebase of the left phallomere (fig. 14

A), where

it terminates in a duct that opens

on

a

membranous

space

between

the

two

middle distal lobes {r, s) of the appendage. Ito (1924) mistakenly says that the duct of the gland opens into the posterior extremity of the ejaculatory duct.

The

phallic glandof Periplaneta aniericana is similar to that of Blatta except that it is subdivided into several

compact

lobes. In Blattella gernmnica the phallic gland consists of a

mass

of coiled tubules (fig. 16

B)

; its long slender duct opens

on

the phallic integu-

ment mesad

of the

mouth

of the sac containing the left phallomere

(E,^).

The

phallic organs.

— The

external genital apparatus of

male

roaches, as of the mantids, consists of genital lobes, or phallomeres, associatedwiththe

mouth

of the ejaculatory duct,

which do

not unite to

form

a single phallicorgan comparable withthat of other

Orthop-

tera.

Two

distincttypesofphallic structureare

found

ⁱⁿtheBlattidae

;

one is characteristic of the Blattinae; the other,judging

from

various published accounts, but principally

from

Chopard's (1920)

compara-

tivestudy of the blattid genitalia,

would

appeartooccur, with various modifications, in

most

of the other subfamilies.

Presumably

inter- mediate

forms

are to be

found between

the

two

types, but it is not necessary to suppose that one has been derived

from

the other, since both types havea similar origin in

nymphal

instars.

The

descriptions of

two

representative species of each type here given can serve only as a basis for a

more

extensive study,

which

might lead to a better understanding; of the natural classification of the blattid subfamilies.

42 SMITHSONIAN MISCELLANEOUS COLLECTIONS

VOL.

96 The

lypt: of ])liallic structure perlaiuinj^ to tlie P>lattinae cousists of a highly integrated

complex

of parts belonging to three phallic organs,

which

apjiearin the

nymph

as three simple lobes of thegenital

chamber

wall immediately surrounding the gonopore. This type of structureisilkistratedinthe following descriptions of Blattaorientalls

and

Periplanetaamericana.

The abdomen

^of anadult male of Blatta oriciitalis (fig. 12

A)

ends with the broadly truncate

and somewhat

emarginate tenth

tergum

above

(XT), and

the large

rounded

ninth

sternum

below (B,

IXS), which

latter bears the elongate styli (Sty).

Beneath

the

margin

of the tenth

tergum

are the paraprocts (C,Papf),

and

a small

membra-

nous area or lobe

(Eppt)

representing the epiproct.

Between

the paraprocts

and

the ninth

sternum

is the

mouth

of a deep cavity, the genital

chamber (GC),

containing the phallic organs. In a

nymphal

male the

abdomen

is relatively short

and

broad

(D) and

the small ninth

sternum

does not completely conceal the paraprocts. If the genital

chamber

ofa median-sized

nymph

^is

opened (E)

^{there will} be seen three small, soft lobes projecting

from

its anterior wall

around

the opening of the ejaculatory duct (Dej).

These

lobes are the left

phallomere

(IPhm)

, the right phallomere

{rPhm), and

the ventral phallomere

{vPhm).

In a later

nymphal

instar

(F)

the phallomeres have increased in size

and

the lateral ones

show

the development of accessorylobes.

The

ejaculatory duct {Dej) opens abovethe base of the broadventral phallomere.

From

this simplebeginningare evolved the extraordinarily

complex

genital organs of the adult roach.

The mature

phallomeres of Blatta orieiitalis, as seen

from

above in their usual positionwithin the genitalchamber, are

shown

at

A

^of

figure 13.

The

right phallomere (rPJim) has taken a

more median

position above the genital opening, the elaborately subdivided left

phallomere

(IPhm) forms

a

group

of lobes

and horny

processes

on

the right,

and

the broad ventral phallomere (vPhni) projects to the right

from

beneath the other two.

The

base of the right phallomere

isproduced

forward on

the right intoadeep pocket _{(y) oi the} genital

chamber

wall,

and

the base of the left phallomere is

sunken

into a similar but shallower pocket

on

the left (s).

Beneath

the right phal- lomere is a deep, transverse, oval cavity

(C)

within a large, strongly

convex

capsularsclerite (A, B, C,

m), which

is normally closed

from

below by a flat valvular sclerite (C, n).

Between

the dorsal right phallomere

and

the left phallomere is an obliquely transverse fold, which, beginning

on

the left (A, _fd), goes

downward

to the right

and expands

onthedorsal surfaceof the ventral phallomere (fig. 14 B, fd).

Within

the lowerend of this fold above the base of the ventral