Dr. Burnett on the Development of Viviparous Aphides. 77 
These phenomena thus interpretated, furnish us an excellent 
key to many others which mame long been regarded as anomalous, 
in the history of developme 
I refer here to the soiled, hibernating eggs ( Wintereier ) which 
are found in many Invertebrates. These I have not seen, but 
they have been carefully deaaribeil by ita ere trustworthy 
observers. ‘These so-called eggs ee of oval masses or cells 
invested with a capsule, but in which no germinative vesicle and 
dot have ever been seen. Structurally, cucseieee they do not re- 
semble eggs, and it is from their form and ulterior development 
only that they have received this name. Moreover, they sustain 
none of the usual relations of eggs to the sexual organs, and, as 
far as I am aware, no one has witnessed their development in the 
ovaries. ‘These bodies have been observed in Hydatina®* and 
sex was once doubted from its infrequent appearance. 
"is [regard these hibernating eggs as merely egg-like buds ex- 
actly corresponding to the germs of the viviparous Aphides. In 
other words, there are in the animals I have just mentioned, certain 
* Ehrenberg, “Die Infusionsthierchen,” iB 413. 
+ Dalrymple, Philos. Trans. 1849 
} Huczley, Quarte erly Jour. Micr. Se. 1852 i, p. 1 
§ Miller, Entomostraca, p. 84. Tab. XI, fig. baL Rt xr, fig. 5. Also 
Ramdohr, rai PANG Natargesch. kulus-Arten, 1805. p. 28; 
Strauss, avec sur les Daphnia, e Mém. du Mus. Fy Hist. Nat., v, p.413. Pl. xxix; 
Jurine, Histoi ° des Moncks s, "18 ~ P 120. ie ah, Oe. By Jurine calls these 
aggregated wie eee de la se 
There is, moreover, reason to. believe that these anomalous oe seme a 
occur in nearly all the E 
My transl. wt my note under § 292, note 
§ Notice may here be given of s some aro : , observations, which Filipi (Ann. Nat. 
Hist. , ix, 1852, p. 461) has far urnished on his Gevelbpeient o a — a eromalide. A Ptero- 
lus ; this larva becomes a pupa, and, after eight or ten days, changes to the perfect in 
sect whi escapes from the ovum, 
It t observations are verified, we have here a case exactly like that of the 
Ajliaee excepting that like the Beste, the intermediate merge 4 form is bert 
low, and takes on none of the zoological peculiarities of the parent. But these sta 
ments need corroboration, for they do not agree with the vere Po of he: ec 
Pieromalus Mate development is well known, See also, the wo imiparous 
enomena related by Siebold of Gyrodactylus ; Siebold and Kolliker’s eitsch. f. wiss. 
L, i, 1849. p. 847. ers te ee ean 0 arr eae 
