Dr. Burnett on the Development of Viviparous Aphides. 71 
Seminis connecting with the oviduct, in which the semen is 
deposited during coition and where it may be preserved without 
losing its vitalizing power, for several months.* Thus, by this 
provision, the males, having copulated with the females in the au- 
tumn, may immediately die, while these last, hibernating, produce 
in the spring, fertile ova; and in the instance of the Bombus 
americana, such a coition suffices for all the three broods which 
are produced the ensuing summer. se 
Another explanation of these curious phenomena, and which 
has attracted some attention, as well from its singularity as from 
the eminence of its propounder, is that of Owen, advanced in his 
Hunterian Lectures in 1843. 
He affirms that the larval Aphides are productive in virtue of 
the successive continuation from brood to brood of a portion of 
the primitively fertilized germ, and which material product or 
€aven is not exhausted until nine to eleven generations. I will 
quote his own language: “In the Aphides the corresponding vi- 
telline cells retain their share of the fecundating principle (which 
Was diffused through the parent egg by the alternating, fissipa- 
tous, liquefactive, and assimilative processes) in so potent a degree, 
that a certain growth and nutritive vigor in the insect, suffice to 
set on foot in the ovarian, nucleated cells, a repetition of the fis- 
Siparous and assimilative process, by which they transform them- 
selves in their turn into productive insects; and the fecundating 
force is not exhausted by such successive subdivision until a 7th, 
ot ? OF llth generation.” This same doctrine, the successive in- 
heritance of a portion of the primary germ-mass from brood to 
oc 
P arthenogenesis, and I will here quote one sentence, not only in 
illustration of this, but to show how different his own observa- 
a. the development of these animals, are from mine, just 
of the yolk in the chick. I at first thought it was 
enclosed in the alimentary canal but it was not so. 
As the embryo grows, it assumes the portion of the ovarium, and 
* For many details o * ; era Si halal Miil- 
n this subject of the Receptaculum seminis, see Siebold, Mu 
Go Arch, 1837, p. 392; also a Wiemann Arch., 1839, i, p. 107, ( Vespa), and in 
1847 — i pa ii, 1840. p. 442, (Culex). See also Stein, Vergleich. Anat. &c. 
- p- 96, 112, oi 
i ant but believe that the anomalous reproductive conditions of the Cynipide 
» at last, have a solution equally as satisfactory. See Hartig, Germars Zeitsch.,u, 
P. 178, and iv, p. 395. See also Sicbold and Stannius CO parative Anatomy, transl., 
4 § 848, notes 1 and 4, 
imale tos 0 the Comparative Anatomy and Physiology of the Invertebrate An- 
s, &c. London, 1843, p. 233. This explanation is lately insisted upon (strange 
Mm his r enogenesis, or the successive production 
: “het? ” 849, res ined ce Oe eae 
Serelate) in his recent work “On Parth ion of 
Procreating a single Ovum, anes 
: 
el, 
i 
