58 



times their length, and were developed into male and female. A 

 small number of eggs were also seen in different stages, within 

 the oviducts and scattered about the bottom of the vessel. 

 These worms correspond with the description and figures in the 

 Micrographic Dictionary under the head of Anguillulidice, and 

 are thus excluded from being the embryos of syngamus. 



Exp. 18. Several embryos taken from the intestinal canal of 

 the earthworm, where they were found surrounded by mucus, 

 were placed in a glass dish of water and kept, as in the foregoing 

 experiment, seven days. These embryos after a few hours coiled 

 themselves up at the bottom of the dish, and for the most part 

 of the time remained in this condition, occasionally uncoiling 

 and moving about a short distance. No growth or development 

 of structure took place. These are the embryos which it is 

 believed are identified as those of syngamus. 



Exp. 19. Placed several embryos from the intestinal canal of 

 the earthworm, like those in the preceding experiment, in an 

 incubator, and kept them at 105° Fahrenheit for seven days, at 

 which time they were alive, but no change of structure or devel- 

 opment had taken place. 



Exp. 20. One pint of blood from a calf was allowed to stand 

 in a glass fruit jar, until the solid portion had settled, leaving 

 the serum at the top. On May 5th, at 9 a. m., one dram of this 

 serum was placed in a Syracuse solid watch glass, with ground 

 edges, containing twenty of the last described embryos. These 

 embryos had been kept in the watch glass in water one week, 

 and were nearly all lying quietly coiled up about its center. The 

 most of the water was removed by a pipette before the serum was 

 added. As soon as this was done, the embryos uncoiled and be- 

 came quite lively, as though they had at last found their natural 

 element. The watch glass was placed in an incubator, covered 

 by another one with ground edges, but leaving a small space for 

 air. The temperature had previously been regulated so as to 

 remain at 105° Fahr. At 9 p. m., on examining them with the 

 microscope, they had slightly increased in size and were com- 

 mencing to moult. On May 6th, at 9 a, m., they were again taken 



