340 



ESSENTIALS OF ZOOLOGY 



In the female the threadlike ovaries join the coiled oviducts which 

 lead forward and join the two uteri. These tubes join in the vagina, 

 which is a short tube leading to the genital pore. 



J770at^ circumes>ophagecc/ 



aterus 



oyanes 



CJtcretort/ p/?ari/nx fer?iCa/ pore //7C>e3C/r7e, docfi/ iva// a/9a^ 



0)^/CfiJCt 



oyar^ 



uterc/5 



va^/rfoc 



pseuotocoe/ 



teatM 



cte/ctas ofeferc/7S 



sem/ncf/ ves/ch 



e/aca/atorf/ dc/ct 



cat/c/e ] tntesUne, 



pseudocoeJ 



ep/oferm/e\ bod^ ivcr// 



y77a3c/e ) ^c/7?//7(y/ yes/b/e 

 cut/cJe 



Inteet/ne' 



Gxcretoru cana/ 



pert/cff 

 o\r/duct 5e^Jae" 



seta/ sac 

 rectu/r? 



oyar^ 

 ner/e cord 



ar?c/i 



s 



Pig. 124. — Internal anatomy of Ascaris lumhricoides. A, Diagram showing 

 lateral view of dissection of female ; B, cross section through the mid-region of the 

 body of the female ; C, longitudinal section of the posterior portion of the male ; 

 D, reproductive system of female; E, reproductive system of male. (From Curtis 

 and Guthrie, Textbook o/ General Zoology, John Wiley and Sons, Inc., modified 

 from Leuckart.) 



Reproduction and the Life Cycle 



The animals copulate, and this time the spermatozoa are intro- 

 duced into the vagina of the female to fertilize the mature ova in 

 the oviducts. A mature female may contain as many as 27,000,000 

 eggs. These eggs pass from the host with the feces. Some workers 

 have reported that each female worm in an infected host may pro- 

 duce a crop of eggs in excess of two thousand per gram of feces. 

 Based on this figure, the daily production is computed to be some- 



