125 



and describes it as being from 2*4 to 2 '8 mm. long by 45 to 50 /x 

 broad, body filiform, terminating posteriorly in a blunt 

 point furnished with bristles; cuticle striated longitudinally. 

 In one sore he found, on dissecting the superficial part, five 

 examples of a larva which he calls the "inconstant parasite." 

 This is described as being 900 jx long by 25 /x broad, cuticle 

 smooth, anus at the base of the tail, and vulva at the posterior 

 third of the body. 



Railliet draws attention to the occurrence of cutaneous 

 lesions in which larvae have been found, but which differ from 

 the "constant parasite" of Descazeaux. He recalls that Ercolani 

 met with embryos of a Nematode in a horse on which were 

 found "umbilicated crusts" about 1 cm. broad and very 

 adherent. The crusts implicated the entire thickness of the 

 skin, and were localized at the lower surface of the body along 

 the linea alba, where there were also many bare patches. In 

 these crusts Ercolani found a small Nematode, which was 

 characterized by keeping its caudal extremity doubled under 

 the body and making frequent movements of abduction. He 

 called the worm Trichina uncinata. Unfortunately no dimen- 

 sions were given. Railliet remarks that Haubner described 

 this condition under the name of "placoregma," and that the 

 affection, which has also been described by Cadeac, presents 

 a very marked resemblance to "summer sores." 



Railliet mentions that Buffard found embryos in 

 oedematous plaques which somewhat resembled the lesions of 

 dourine. These embryos measured 80 to 90 jul long by 3 "5 

 to 4 ju, broad. Buffard believed these to be the embryos of 

 Filaria papillosa fSetaria equina), but Railliet shows that he 

 was mistaken. 



Railliet believes that the embryos found by Ercolani and 

 Buffard are embryos of Habronema. 



Further, Railliet believes that the "inconstant parasite" 

 of Descazeaux is an early larval stage of Habronema, resem- 

 bling stag-e 2 of H . muscae, as described by Ransom. 



Fayet and Moreau described a larva measuring 2'5 to 

 3'5 mm. long by 50 to 90 [l broad, which possessed longitudinal 

 striations, but spines on the caudal extremity were not 

 mentioned. Railliet believes that if the larva really lacked the 

 covering spines at the tip of the tail it would fall into one of 

 the stages between 3 and 5 of H. muscae, as described by 

 Ransom. 



The main part of Railliet's paper deals with the classifica- 

 tion of the larval Nematode found in "summer sores." The 

 fact that the larva possesses a spinous tip at the end of the 

 tail has enabled Railliet to definitely place it in the super- 

 family Spiruroidea. The larva corresponds closely to the sixth 



