SYNGAMUS TRACHEALIS. 



EXPLANATION OP FIGURES. 



Fig. 1— Adult, male and female Syngamus, united (natural size and enlarged 12 diameters). 

 A, male; B, female, each showing the head, esophagus and intestine. In the female 

 may be seen the uterus and ovarian tubes filled with eggs. In the male, the seineniferous 



tube. 



Fig. 2.— Smallest pair of Syngami ever seen (enlarged 50 diameters). A, male; B, female. 



Fig. 3.— Embryo of Syngamus removed from the earthworm and kept in the blood serum of 

 a calf, in an incubator, at 105° Fahr., between four and five days. About moulting the 

 second time after being placed in the serum. Embryo lying within the exuviae. See 

 structure of mouth of embryo, and also in the exuviae (enlarged 200 diameters). 



Fig. 4.— Embryo of Syngamus removed from the earth worm and kept in the blood serum of 

 a calf, in an incubator, at 105° Fahr., for 24 hours. About moulting the first time after 

 being placed in the serum (enlarged 200 diameters). 



Fig. 5.— Embryo of Syngamus removed from the lung of a chick fed earthworms containing 

 the embryos. This embryo had just entered the lung (enlarged 200 diameters). 



/7„ 6.— Embryo of Syngamus removed from the intestinal canal of an earthworm (enlarged 

 200 diameters). 



jJ7 ff- 7.— Embryo of Syngamus within the egg < enlarged 200 diameters). 



Fig. 8.— Egg of Syngamus in the mulberry state (enlarged 2li0 diameters). 



jr tc ,. <». — Perfect egg of Syngamus immediately after passing out of adult female (enlarged 

 200 diameters). 



/,•,„_ id— Caudal pouch of male. Observe the eight principal ribs which are subdivided SO 

 there are eighteen divisions at the circumference, each extremity of which i> expanded 

 into a sucker. These suckers project through the broad margin of the pouch which is 

 closely applied around the vulva of the female, to which they enable it very firmly to 

 adhere. The posterior part of the circumference of the pouch is cut out and has no suck- 

 ers. Here is where the eggs pass out. 



