TRICHINA SPIEALIS. 353 



similar to those of the cat. At the same time, Herbst leaves it 

 undecided, with regard to the former, whether it is derived from 

 an indigenous species of Filaria or from the Filaria medinensis. 

 The latter appears to him to be inadmissible, on account of its 

 comparatively frequent appearance in England ; an opinion in 

 which Herbst will have but little support amongst zoologists and 

 surgeons. 



3. The Trichinae of the mole and frog, which, according to him, 

 are identical, and with regard to which Herbst himself states that, 

 whilst the Trichina of the frog might be derived from Filaria 

 neglecta and rubella, no one has yet found a Filaria in the mole. 



It appears to me that it would have been better, recollecting 

 Reinhardt's observation upon the spleen of the mole, to con- 

 sider the Trichinae of the mole as the descendants of a species of 

 nematode worm, which, according to the form of the egg, must 

 be ascribed to the Trichosoma as Von Siebold thought, or to the 

 Trichocephali. This only furnishes a fresh support to my opinion 

 expressed above, that it is certainly incorrect to regard the Trichinae 

 exclusively as the young brood of the Filarice, whilst they may 

 equally be descended from other Nematoda. Besides the form, a 

 circumstance which determined me, with regard to the collocation 

 of the Trichinae and Trichocephali, is the fact that hitherto no 

 Trichosoma which might come in question here, besides and 

 together with the Trichocephali, have been found in the human 

 body ; this, certainly, ought to be further inquired into. 



It remains to mention that Herbst adopts a triple mode of 

 life for the Trichinae. 1, in the encysted state; 2, quite free, 

 which are regarded by Herbst as living free and having escaped 

 from eggs borne by the blood; and 3, half-free, in sacs of the 

 peritoneum, and much larger than the first and second forms. 



Experiments in the administration of Trichinae gave Herbst 

 the following results : 



Three dogs, to which the flesh of a trichinous dog was given 

 as food, all became trichinous. 



In pigeons fed with trichinous mole's flesh, Herbst found many 

 free Trichinae, eighteen days after the feeding, in the muscles of 

 the neck, wings, and thighs. A young daw exhibited free 

 Trichinae in all the voluntary muscles, eleven days after feeding 

 with the same flesh. After feeding several weasels with frogs 

 and moles which had not been examined for Trichinae, their 

 muscles also exhibited Trichinae. 



