464 REPORT ON ZOOLOGY, MDCCCXLIV. 



was transformed into a crystalline vitreous substance ; Svitzer 

 in other respects, observed the animal erroneously, since he 

 regards the longitudinal streak indicating the cavity of the 

 muscular oesophagus, and which is almost invariably pre- 

 sent in the young nematoda, as the penis. Svitzer believes 

 that a series of minute corpuscles might be regarded as ova, 

 but which the Reporter explains as being the remains of the 

 vitellus. Klencke also (Ueber die Contagiositat der Einge- 

 weidewiirmer, p. Ill) has fallen into the error of regarding 

 the Trichina spiralis as a completely developed and sexually 

 mature nematoid worm. He has even carried his error 

 farther, and has made experiments of injections with the 

 granular contents of this Trichina, which he has taken for 

 ova. But what can be said with respect to this, when 

 Klencke asserts that these experiments have actually been 

 successful in his hands, and that by the injection of these 

 supposed ova he has transplanted the Trichina spiralis 

 from one dog to another? He also supposes that he has 

 found Trichina spiralis very abundantly in Fish, Snakes, 

 Birds of prey, and Mammalia, which may be readily be- 

 lieved, since young asexual and encysted Nematoda, which 

 the Reporter (Archiv, 1838, Bd. i, p. 312) has described as 

 Trichina, are found so universally distributed. According 

 to Kleucke (1. c. p. 112), it would appear that the occurrence 

 of Trichina spiralis is not constantly limited to the volun- 

 tary muscles, and that they also extend to the muscles of 

 the vegetative system, of which one may be convinced in 

 animals, and even in man. This may be granted with 

 respect to animals, but where has Klencke observed it in 

 man? 



Dubini believes that he has found an entirely new human 

 Round-worm. (Omodei Annali univ. di medicina. Aprile, 



1813. torn, cvi, p. 5. Schmidt's Jahrbiicher. Bd. 41, 



1814, p. 186.) This worm, which has been named by its 

 discoverer Agchylostoma duodenale, is 44 lines in length, and 

 was met with in at least 20 among 100 bodies, in the 

 duodenum and upper part of the jejunum. Like the 



