PACHYDERMATA 409 



system while in the embryonic condition." I think that Dr 

 White deserves great credit for his correct diagnosis of the 

 species, and all the more so because he was evidently not 

 acquainted with Diesing's original memoir. He expressly 

 speaks of the " scanty descriptions " hitherto given of the worm. 

 As Dr White had accurately determined the species in the 

 presence of an American Scientific Society, it is remarkable 

 that neither Verrill nor Fletcher should have identified the 

 worm. 



On the 10th of January, 1871, I received a letter from 

 Prof. W. B. Fletcher, of Indianapolis, Indiana, U.S.A., and in 

 it he announced that he had " found a worm " infesting the 

 hog. The parasite was so abundant in swine that he obtained 

 it in " nine out of ten hogs " which he had examined. Dr 

 Fletcher sent me specimens of the worm for description and 

 identification, when I at once recognised them as examples of 

 Diesing' s Stephanurus dentatus. As Dr Fletcher's first commu- 

 nication to myself was undated I do not know precisely when 

 he first encountered the worm, but it was in 1870. In that 

 same year Prof. Verrill received specimens of the worm. He 

 says that they were received from Dr J. C. White. Failing to 

 identify the parasites as Stephanuri, Verrill (making no allusion 

 to the ' Proceedings of the Boston Society ; ) not unnaturally 

 supposed he had to deal with an entozoon that was new to 

 science. Accordingly he immediately described and figured 

 the worm under the combined title of Sclerostoma pinguicola. 

 If these data are correctly given, the re- disco very of the worm 

 in America was due to Dr J. C. White j its identity with 

 Stephanurus being subsequently acknowledged by Diesing, and 

 afterwards, quite independently, by myself. I gather this 

 partly from Diesing' s ' Kleine helminthologische Mittheilungen ' 

 (s. 281), published as a supplement to his ' Revision der 

 Nematoden ' (186061). Until quite recently Diesing's 

 recognition of the identity of White's parasites with Stephanuri 

 was unknown in America. My conclusions arose from an 

 examination of the actual specimens, whereas Diesing was 

 entirely guided by White's description. In this connection, 

 moreover, a still more interesting re-discovery remained to be 

 recorded. The original announcement which I made in the 

 f British Medical Journal ' for January 14th, 1871, was followed 

 by another in the same periodical for September, 1871. As 

 stated in my second letter and repeated in my notice of Krabbe's 



