AND MORPHOLOGY OF APHIS. 197 
* T am indebted to my friend Mr. Haliday for the following translation of an extract 
from Erichson’s Bericht, &c., 184.4, Ent. Zeitung, pp. 9, 81, 133, 410. Ratzeburg observed 
a species of Aphis on the Birch, which continued to produce a living progeny from 
August into winter without either male or female appearing. Bouché and Kaltenbach, 
in explanation, remark that the males in this family are not always winged. However, 
in the May following, Ratzeburg, continuing his observations, found the winged females, 
and afterwards (in October) winged males also, which paired with them. The species was 
then identified as 4. oblonga, Von Heyden. For the male to pair with a winged female 
(continues Mr. Walker) is a very unusual case among Aphides*.” In fact, I have hitherto 
found, in Mr. Walker’s long list of 101 species, no case of an oviparous winged female 
observed by himself. Mr. Walker states as a known fact, that Aphis Rose habitually 
lives through our mild winters. 
In his work on ‘ Parthenogenesis’ (1849), Prof. Owen modifies his previous statement 
so far as to say, in a note (p. 59), that the perfecting of the female generative organs in 
Aphis “is not attended by the acquisition of wings; or if they be developed in the ovipa- 
rous female, they soon fall. I have, however, retained them in the diagram for a better 
illustration of the analogy. Many of the virgin viviparous Aphides acquire wings, but 
never perfect the generative organs.” 
The diagram referred to exhibits two figures, (b) and (i), which, for anything that 
appears in the text, might be taken to be the author's representation of male and female 
Aphides. On comparing them with the illustrations of Morren's memoir, however, it is 
at once obvious that they are copies of his figures 1 and 2, of which fig. 2 does really 
represent a male; while fig. 1, on the other hand, is not an oviparous, but a viviparous 
female. In the explanation of his figures, Morren indeed merely says of fig. 1, “ Femelle 
vue en dessous ;”” but it requires no great amount of attention to his text to observe his 
distinet statement (already quoted), that the winged female is viviparous, and not ovipa- 
rous. I am obliged to be thus particular in explaining these unusual circumstances, as 
otherwise the existence of a typical figure of a winged oviparous female Aphis, in the 
work of an accredited author, might be brought forward as conclusive evidence of the 
ordinary occurrence of such femalest. 
* On turning to Ratzeburg's notice in the * Entomologische Zeitung, 1844, p. 410 (Fortgesetzte Beobachtungen 
über die Copula der Blattläuse), which is the last word of the correspondence between Kaltenbach, pons and him- 
self on this subject, I find his precise words to be these :—'* Wie gross war daher mein Erstaunen, als ich bei meiner 
ersten, nach der Rückkehr angestellten Excursion, am 22 October gleich auf den ersten Blick unter der Menge von 
ungeflügelten Individuen, welche die des vorigen Jahres bei weitem übertraf, auch geflügelte Puppen und geflügelte 
Männchen bemerkte, und wie gross war meine Freude, auch gleich darauf mehrere der letztern in der Begattung zu 
finden, also in einem Acte, den ich bei Blattläusen selbst noch nicht hätte beobachten können.” Subsequently, Ratze- 
burg states that he was able to observe the copulatory process early and late, at any time between the 22nd October 
and the 16th November. - å 
It will be observed that there is not a word here about such winged females as Ratzeburg, in å —— 
states he saw in May of the same year. The winged pupæ are apparently, from the context, the nn. Bi " em 
and the forms with which the winged males copulated were the wingless females. So that here, as = : å " 3 sd 
posed cases of winged, oviparous true Aphides I have looked into, the evidence, when closely examined, bre er i 
t Professor Owen, in the last edition of his * Lectures on the Invertebrata,’ p. 410, quotes Léon Dufour as having 
. » i a > , i A les 
witnessed the coitus of the male Aphis * with the winged female. The reference is to ger så in Anna 
