THE ANATOMY 0¥ THE ADULT MOSQUITO 



107 



The genital organs of the female consist of a pair of 

 more or less spindle-shaped bodies, which, in the unimpreg- 

 nated insect, are contained mainly in the last abdominal 

 segment, and lie obliquely in it on either side of the middle 

 line, their distal extremities being supported by a sort of 

 ligament springing from the common fibrous lining of 

 the segment. They contain a large number of soft closely 

 packed ova in various stages of development, those nearest 

 the opening of the oviduct being the most advanced. They 



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Fig. 26. — Generative Organs of a Gravid Female Mosquito. 



A. Generative organs of C. fatigans, ? x 18 diams. ; or, right ovary and 

 oviduct full of mature ova ; ol, outline of left ovary ; g, last ganglion of 

 abdominal chain ; d, ovarian ducts ; ocl, common oviduct ; st, spermo- 

 thecse ; op, ovipositor ; B, spermatozoa from the spermotheca, x 450 diams. ; 

 C, a mature ovum, x 45 diams. ; b, portion of coat of ovum proper, show- 

 ing its spinous structure. 



are richly supplied with tracheae, supplied from the stigmata 

 of the penultimate segment, as well as with large nerve 

 threads from the last abdominal ganglion. 



When further advanced, the ovaries and their ducts take 

 up a large share of the cavity of the abdomen ; forming a 

 pair of large, lobulated masses. At this stage, very little of 

 the true ovarian tissue can be distinguished, almost all that 

 can be seen being the enormously dilated funnels of the 

 oviducts. Each egg consists of the ovum proper, clothed 

 in a chitinoas envelope closely covered with minute 



