À. 
236 PROF. HUXLEY ON THE AGAMIC REPRODUCTION AND MORPHOLOGY OF APHIS, 
e 
Tas. XXXIX. 
Aphis Pelargonii. 
Fig. 1. a. Nearly full-grown fœtus, extracted from its investments, and somewhat unfolded: 4. anus, 
whence the alimentary canal is seen taking a curved S-like course to the mouth. B. Terminal 
chamber of one of the pseudovarial cæca of this embryo. 
Fig. 2. The mouth of this embryo seen from below. The “labium” (vr') already appears as a large single 
process bilobed at its free end. 
Fig. 3. Side view of the head of a similar embryo, showing the relative position of the different append. - 
ages and the course of the æsophagus. ; 
Fig. 4. A nearly full-grown fætus in its pseudovitelline membrane: r. the pigment of the eye; s. rudi- - 
mentary siphons. : 
* Fig. 5. A partially diagrammatic figure of the wingless viviparous form of Aphis Pelargonii. The Roman - 
numbers indicate the typical somites of the body and their appendages; the other numbers — 
mark the abdominal somites. A, Anus; c, genital aperture; s. siphon. Lo 
på 
Tap. XL. 
Reproductive Organs of the oviparous Aphis (Vacuna dryophila). 
Fig. 1. The female organs entire. One ovarian cæcum only is represented ; and I have purposely selected — 
one of those, the ovarian glands in whose apical chamber are very similar, at first sight, to ova. — 
A. Anus; B. vulva; c. vagina; p. oviducts j E, F, G, H, 1, K. chambers of the ovary ; L. ovarian Es 
glands; m. colleterial glands; x. spermatheca; 7, 8. seventh and eighth abdominal sterna. — 
Fig. 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 (x) ; o!. germinal vesicle of 
ovum in 1; and o". of ovum in H ; P. epithelium; -g. cord-like secretion of ovarian gland, l; 
l. inner capsule of ovarian gland. > Ne 
Fig. 3. The end of another ovarian cæcum, showing very distinctly the apparent continuity of the cord, — 
9, 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. a. 
Fig. 4. a. Posterior extremity of the ovum unaltered: r. chorion; s. tubercular elevation; f. append- 
age; lg its gelatinous, investment; v. rod-like bodies imbedded therein ; v. the same more 
tented, B. Anterior end of the ovum after the action of potash; y. papillary elevation ; 
* internal markings of the chorion (r); w. vitelline membrane; +. vitellus. c. Posterior 
extremity treated in the same way: y, micropyle ? 3 
a -o HUE 
