452 THE INSECTA. $ 350, 
and many Geocorisae, the secretory apparatus consists of two round gland- 
ular sacs,” while, with the Cicadidae, it is a single, long flexuous tube. 
The viviparous Aphididae differ from those which are oviparous, in that 
their eight ovarian tubes are multilocular, and their oviducts entirely with- 
out appendages; while with the second or oviparous, these eight tubes are 
unilocular, and there is a seminal receptacle and two sebaccous glands. 
With the Diptera,“ the ovaries consist, usually, of numerous short, 
three or four chambered tubes. With only a few species, these tubes are 
long and have eighteen to twenty chambers."” The disposition of these 
tubes varies considerably. With some, they are simply terminal to the 
short oviduct; while with others they form one or more series on the 
sides of these organs, which, then, are longer. 
The Receptaculum seminis presents the most varied forms,“ it is usu- 
ally, triple, rarely simple or double, and is lined with a horny, brown 
substance. It has a round, pyriform, or oblong shape, and, in this last 
case, is often flexuous or spiral. The seminal ducts, which lead from 
the receptacles to the vagina, are sometimes isolated, and sometimes united 
into one or two common ducts before entering the vagina. Directly below 
them on each side, are the points of junction of the two secretory organs, 
which, always present with the Diptera, consist of two simple, rarely 
ramose tubes, whose very small excretory ducts have, exceptionally only, a 
vesiculiform dilatation.“? The Bursa copulatrix appears to be wanting with 
all the Diptera. But, with many Muscidae, the vagina has, as a seminal 
receptacle or uterus, a spacious, and sometimes two-lobed reservoir in which 
the fecundated eggs are accumulated in great numbers, and remain until the 
larvae are sufficiently developed to be hatched, making these animals vivi- 
parous.” With certain species of Tachina, this uterus presents a remark- 
able form ; the vagina is very long, spiral, and of equal size throughout ; 
and, at certain periods, is crowded with larvae or small eggs. With the 
pupiparous Hippoboscidae, the female organs are formed on an entirely 
special type, corresponding with the remarkable mode of the reproduction 
7 See L. Dufour, Recherch. loc. cit. Pl. XIV. 
XV. 
8 See Meckel, Suckow, L. Dufour, Doyere, 
loc. cit. 
9 See my researches in Froriep’s neue Notiz. 
XIL. p. 307. Dutrochet (Ann. d. Sc. Nat. XXX. 
1833, p. 204, Pl. XVII. C. fig. 1), it would appear, 
has unwittingly figured the genital organs ef an 
oviparous Aphis, by taking the seminal receptacle 
for a sperm-secreting organ. In this way he was 
led to regard the viviparous Aphididae as her- 
maphrodites. 
10 For the internal female organs of the Diptera, 
see Z. Dufour, Ann. d. Sc. Nat. I. 1844, p. 253, 
and especially Loew, Iorae anatom. p. 61. 
1l Ephydra and Tachina ; see Loew, loc. cit. 
Taf. LV. tig. 3, 10. 
12 For the Receptaculum seminis of the Dip- 
tera, see Siebold, in Mudder’s Arch. 1837, p. 414, 
Taf. XX. fig. 7-10; and especially Loew, loc. cit. 
p. 89, Taf. IV.-VI., and in Germar’s Zeitsch. III. 
p. 386, Taf. III.; the numerous figures of this 
author will give some idea of the inexhaustible va- 
riety of forms of these organs. When L. Dufour 
(Ann. d. Sc. Nat. I. 1844, p. 262) would regard the 
seminal receptacle as a reservoir of the neighboring 
secretory organs, it is evident that this distinguished 
entomotomist must have entirely omitted a micro- 
scopical analysis of the substances found in the 
various glands and other organs of Insecia, 
13 The Receptaculum seminis is simple with 
Pulex, Empis, Dolichopus, and Hilara; and 
double with Piophila, Stomoxys and Borborus. 
14 See Siebold, and Loew, loc. cit. These gland- 
ular appendages secrete with certain Tipulidae a 
considerable quantity of gelatinous substance which. 
envelops the eggs and binds them in a kind of col- 
lar. These collars, which are deposited in the 
water, have for a long time been figured by bot- 
anists among the algae under the name of ‘Gloeo- 
nema. 
15 There are viviparous species in the genera 
Musca, <Anthomyia, Sarcophaga, Tachina, 
Dexia, Miltogramma, &c.; see my memoir in 
Froriep’s neue Notiz. III. p. 337, and in Wieg- 
mann’s Arch. 1838, I. p. 1973; also my Observat. 
quaed. Entom. &. p.18. ZL. Dufour (Ann. d. Sc. 
Nat. I. 1844, p. 261) has designated this reservoir 
as Réservoir ovolarvigere ; see also his Hist. d. 
Métamorph. et d. Anat. d. la Piophila petasionis, 
Ibid. p. 882, Pl. XVI. fig. 16, g. Loew (Horae- 
anatom. ‘lab. IV. fig. 9, 11, 14, Tab. V. fig. 18) 
has figured analogous uteriform reservoirs with 
Musca, Dexia, Piophila and Psila. 
16 This long spiral-form vagina, which was for- 
merly described as an ovarium spirale, is found in 
Tachina fera, tessellata, grossa, vulpina, hae- 
morrhoidalis, &c.; see my memoir in Wiege 
mann’s Arch. loc. cit, p. 194, and Réaumur- 
Méui. LV. 10 mém. p. 412, Pl. XXIX. fig. 7, 8 
