ON THE AGAMIC REPRODUCTION AND MORPHOLOGY OF APHIS 39 
§ 3. Description of the Oviparous Female Aphis and of the Development 
of the Ovum 
Throughout the two months during which the Ivy-leafed Gera- 
nium, on which my viviparous Aphzdes are living, has been in my 
possession, neither males nor females have made their appearance. 
Therefore, being extremely desirous to compare the process of the 
development of the germ with that of the ovum, before completing 
this paper, I began in the last days of October to seek for oviparous 
females of some other species. 
An QOak-teee in the Zoological Gardens at length supplied me 
with that which I sought. The small twigs and leaves afforded 
habitation to a number of minute wingless Apfzdes, all so nearly 
equal in size that I did not doubt their non-viviparous, and hence 
in all probability their oviparous character. 
Microscopic examination fully confirmed my suspicions; for not 
only were the Apfzdes full of ova, but I found multitudes of similar 
ova adhering to the plant in the axils of the leaves, and more 
particularly between the outer bracts of the buds.! 
These Aphides were very different from my viviparous species. 
They were about #,th of an inch in length. The general hue of the 
body was pale green; but it was diversified in the dorsal region by 
four longitudinal rows of blackish rounded spots, one spot in each 
row being seated on the tergum of most of the somites, from the 
prothorax backwards. Hence there were nearly as many transverse 
rows of four spots each, as segments of the body. The two median 
spots in each row were larger, and situated close to the middle line. 
The external spots were more upon the sides of the body. The spots 
upon the mesothorax, and thence to the sixth abdominal somite 
inclusive, were the largest and most conspicuous. Each spot was 
constituted by a dark elevation of the integument, which supported 
a tuft of long sete, knobbed at their extremities like the glandular 
hairs of certain plants. The hairs were not confined to these 
localities, however, but were scattered over the head and other parts of 
the body. The eyes were red, and produced into a small tubercle on 
their posterior margins. The distal portions of the antennz, and the 
1 I do not think that my 4fdzs of the Oak is identical either with that described by 
Réaumur, or that described by Bonnet. None of my specimens attained the size of theirs, 
nor do either of those writers mention the peculiar dorsal markings of my species: further- 
more, the proboscis in both Réaumur’s and Bonnet’s was long ; it mine it is very short. The 
proper specific names of both the Aphzdes alluded to in this memoir will be discussed ina 
final note. 
