ON THE AGAMIC REPRODUCTION AND MORPHOLOGY OF APHIS 
Fig. 
Fig. 
Fig. 
Fig. 
lig. 
Tas. XNNVII. [PLATE 3]. 
Aphis Pelargonie. 
1. Embryo enclosed within its pseudovitelline membrane. The pseudovitellus has 
aggregated over the abdomen, and more or less completely left the thorax. Letters 
as before except—s. the first larval integument’; 26, labrum; a¢. antenna ; Iv’. 
mandible ; v’. first maxilla; vi’. second maxilla; vil’. 
, 
IX’. 
first, viii’. second, and 
third thoracic leg. 1a. The same embryo seen? from below. 
2. Embryo of the same size, viewed from below and the side, the blastoderm unfolded,. 
and the appendages separated. 
Highly magnified view of part of the pseudovitellus, and of the rudiment of the 
pseudovarium, in an embryo ,/jth of an inch in length. 
as 
g. 4. Embryo 4th of an inch, enclosed in its pseudovitelline membrane. 
1 
. §. Embryo 4th of an inch, in its pseudovarian chamber. 
Tas. XXNIX. (PLATE 4]. 
Aphis Pelargontt. 
1. A. Nearly full-grown foetus, extracted from its investments, and somewhat unfolded : 
z, anus, whence the alimentary canal is seen taking a curved S-like course to the 
mouth. 8B. Terminal chamber of one of the pseudovarial ceca of this embryo. 
g. 2. The mouth of this embryo seen from below. The ‘“‘labium” (v1') already appears as 
a large single process bilobed at its free end. 
. 3. Side view of the head of a similar embryo, showing the relative position of the 
different appendages and the course of the cesophagus. 
. 4. A nearly full-grown foetus in its pseudovitelline membrane: 1’. the pigment of the 
eye; s. rudimentary siphons. 
. 5. A partially diagrammatic figure of the wingless viviparous form of Aphis Pelargonit. 
The Roman numbers indicate the typical somites of the body and their appendages ; 
the other numbers mark the abdominal somites. A. Anus; G. genital aperture ; 
s. siphon. 
Tas. NL. [PLATE 5]. 
Reproductive Organs of the oviparous Aphis (Vacuna dryophila). 
1. The female organs entire. One ovarian ceecum only is represented; and 1 have 
purposely selected one of those, the ovarian glands in whose apical chamber are 
very similar, at first sight, to ova, aA. Anus; B. vulva; C. vagina; D. oviducts; 
E, 1, G, H, I, K. chambers of the ovary; L. ovarian glands; #. colleterial glands ; 
2. spermatheca ;. 7, 8. seventh and eighth abdominal sterna. 
2. The three anterior chambers of an average ovarian cecum, Letters as before, with 
the addition of—o. germinal vesicle of the nascent ova in the terminal chamber (kK) 5. 
o’. germinal vesicle of ovum in I; and 0”. of ovum in H; #. epithelium; g. cord- 
like secretion of ovarian gland (/); 2’. inner capsule of ovarian gland. 
3. The end of another ovarian cxecum, showing very distinctly the apparent continuity 
of the cord, g, with the ovum in the*third chamber. The granules of the viscid’ 
vitelline mass (which is surrounded by no membrane) are so numerous as to hide the 
germinal vesicle. 
4. A. Posterior extremity of the ovum unaltered: ~. chorion; s. tubercular elevation ; 
¢, appendage ; w. its gelatinous investment; 7. rod-like bodies embedded therein ; 
uv. the same more magnified. 8B. Anterior end of the ovum after the action of 
potash ; y. papillary elevation ; +. internal markings of the chorion (7); zw. vitelline 
membrane; «, vitellus. c. Posterior extremity treated in the same way: 3’. 
micropyle ? 
