121 



The sporozoits appear as fusiform bodies witli 

 a Central red mass of chromatin. They are about 

 14 M in length, with one end often more pointed 

 than the other. 



Wash off the oil with xylol, dry and label. 



The Reproductive System 



To Examine the Spermatheca (Fig. 39). — By 

 pressing with the edge of the triangular needle 

 cut off the extreme tip of the abdomen — the last 

 or eighth segment only. Place this in a very, small 

 drop of salt solution, and tease the fragment 

 carefully apart. A small black granule (In Culex, 

 three) will be seen. Isolate this as much as 

 possible from other tissue and cover with a cover- 

 glass. 



Observe, under a low power, a brown chitinous 

 ball. Press firmly on the coverglass so as to rup- 

 ture it. Examine under one- twelfth inch. 



Observe the masses of fine hair-like actively 

 motile bodies, if (as is probably the case) the 

 mosquito has been fertilized. Isolate some of 

 these ; they possess the characters of spermatozoa 



(Fig. 39)- . 



Examine the spermatheca of a mosquito 

 newly hatched ; it does not contain spermatozoa. 



To Examine the Ovaries 



Examine the ovaries of a number of mos- 

 quitoes caught in the room, etc. 



Observe that when the ovaries nearly reach 

 maturity they are readily detected as white areas 



