162 



a f«i\v «layH, and the embryos are very similar in their general form to those of Schroa- 

 ioina tetracanthum. They .are cylindroid, subobtnse at the anterior extremity, and 

 provided with a narrow tail mnch shorter than those of the y onng scJerostomes of the 

 horse. They move, besides, in the same manner as the latter. They can live a long 

 time in the fecal material of ruminants when they are not dried, and in this condition 

 they grow. Some young Sclerostomes which, after hatching, were 0.35™'" long to 

 0.50""" have been found in the droppings of sheep. After having been kept damp two 

 and a half months these were from O.GG to 0.78"i'" long. Their skin, which is folded 

 on the surface of the body, appears to indicate that, like the fiderostomea of the horse, 

 they are prepared to ftndergo a molt. The young Sclerostoma hypostomum can live a 

 long time in water after having reached a definite size in the fecal material of rumi- 

 nants. 



We have not yet observed cysts within the mucous membrane of the large intes- 

 tine of sheep.* Bnt as the Sclerostoma hypostomum are in far less numbers of 

 ruminants than S. equinum or S. tetracanthum in the horse, we can not yet draw 

 any conclusion from the negative result of our researches. We will not say then at 

 present whether the Sclerostomes of ruminants pass the second phase of their exist- 

 ence in cysts, or whether they are developed in the intestinal canal itself in the 

 midst of alimentary material which is found contained there. The eggs of the ScJe.r 

 rostomes of ruminants taken directly from the uterus of females and preserved in 

 water at a temperature of from 12 to 20"^ C. (about 55 to 70*^ Fah.) hatch at the end 

 of four or live days after having undergone all the series of successive modifications 

 which are alike observed in the eggs of Sclerostomes of solipeds. 



The ouly possibility of error in Baillet's experiments is tbe indentifi- 

 catiou of the species with which he was dealing, for he writes : 



It (5c/ero8/oJ«« /ii/^JOs/omMmjis above all very frequent in sheep. There are often 

 found individuals, probably younger, whose mouth, entirely terminal, is less widely 

 open, and provided with a single rank of teeth still less numerous. These worms 

 also lack a pharyngeal capsule, and often carry a membranous swelling on the sides 

 of the head. 



The above describes (Esopliagostoma venulosum quite well, and when 

 the learned helminthologist did not experiment with eggs taken directly 

 from the adult worm he may have had to do with the eggs of either. 

 This would account for the similarities found between some of the 

 young embryos experimented with and those of Sclerostoma tetracan- 

 thum. (The author is of the opinion that the last named species should 

 be classed with the Gi]sophaf)o.^toma instead of the Sclerostoma.) 



The life history of this species is, that the eggs are scattered by the 

 sheei>, that they then develop somewhat, and without the need of any 

 secondary host are capable of further development in sheep when taken 

 by them along with the food or drink, and that in the large intestine of 

 the latter they may or they may not make tumors during their embry- 

 onic stages. 



The prevention and treatment is the same as for other intestinal 

 worms. 



* This indicates that (Esophagostoma Columhiaitum has not been observed in France.^- 

 C. C. 



