1861.] DR. W. BAIRD ON A SPECIES OF SCLEROSTOMA. 271 



dently P. lalifrons) they speak of as "big yellow fellow," the other 

 as being smaller and dark ; they also say that the impressions of 

 their feet in the sand-tracks leading to their burrows bear a striking 

 resemblance to those of the foot-prints of a young child. The flesh 

 they describe as being like pork, and excellent eating ; they are ex- 

 tremely difficult to obtain on account of their great timidity. The 

 usual plan is to make a screen of boughs in the vicinity of their 

 haunts, behind which the natives conceal themselves ; and then, if 

 not killed on the spot, they will scramble to their holes, from whence 

 it is utterly impossible to dislodge them. 



Collingrove, South Australia, 

 April 1861. 



2, Notice of the Occurrence of Sclerostoma equinum ? 

 IN the Testicle of the Horse. By W. Baird, M.D., 

 F.L.S. 



The entozoon known by the name of Selerostoma equinum or ar- 

 matum has long been known as infesting the Horse. According to 

 Rudolphi, Dujardin, and Diesing, it is very common at all seasons 

 of the year in the large intestines of that animal, as well as in the 

 Ass and Mule. It occurs also, though more rarely, in the duodenum 

 and pancreas, and a smaller variety is not uncommon in the aneu- 

 rismal sacs of the mesenteriac and ccEliac arteries of these animals, 

 which appear to be liable to that disease. As far as I am aware, 

 however, this parasitic worm has only been once observed, and that 

 by Gurlt, as occurring in the testicle of any of these animals. This 

 author has recorded his having found it in the tunica vaginalis of the 

 Horse. Lately a specimen of what appears to be another variety of 

 this species was received by Professor Owen from a gentleman who 

 had taken it from the substance of the testicle of a young colt which 

 had just been gelded. Only one individual'was sent — a female ; and 

 though it differs somewhat from the ordinary specimens of the Sele- 

 rostoma equinum in the horse, as characterized by the authors men- 

 tioned above, I am unwilling to describe it from a single individual as 

 a distinct species. The specimen is about an inch in length, and is 

 strongly marked with transverse rings, which encircle the body, but 

 appears destitute of the longitudinal striae which Rudolphi and Du- 

 jardin describe as distinguishing, the equimim. The circular rings 

 on the centre of the body are about the fourth, but nearer the head 

 only a third, of a millimetre apart from each other ; whilst in the 

 ordinary specimens of equinum they are described as being very fine, 

 and according to Dujardin only 0"0043 mill. The tail, too, is much 

 more obtuse than in the ordinary specimens of the equinum, and the 

 whole animal is more robust, though not longer. The specimen 

 appears to be an immature individual ; and as I have not been able 

 to refer to Gurlt's notice of the specimens he found in the tunica 

 vaginalis of the testicle of the horse, I must satisfy myself at present 

 with merely recording the fact of its being found in this countrv 



