PARASITICAL GROWTHS ON LIVING AXIMALS. 151 



tuents of these crusts, impossible to hesitate in ascribing their contents 

 to that division of animated nature ; for according to the analysis of 

 Thenard, they contain 



70 Albumen. 

 17 Gelatine. 

 5 Phosphate of lime. 

 8 Water and loss. 



100 



a composition certainly more animal than vegetable. With regard to 

 this, also, it is interesting to refer to the paper of M. J. B. Desmazieres,* 

 in which the genus Mycoderma, founded by Persoon in 1822, is for the 

 first time accurately described and figured. He describes five species 

 occurring in various vegetable infusions. The marked similarity of the 

 figures of some of these species, with the Mycoderm of Tinea, is suffi- 

 ciently curious, viz. those of M. glutinis farinula and M. cerevisice, or 

 those occurring in flour-paste or sour beer (PI. I, fig. 2). M. D., whose 

 paper is well worthy of perusal, considers, from his having observed 

 the globules of the Mycodermata occasionally in active motion, that 

 they are of animal nature, and gives the following definition of the genus : 

 MYCODERMA. Desmaz. Ann. Sc. Nat. Tom. X. \e Ser. p. 59. " Ani- 

 malcula monadina simplicissima, hyalina, gelatinosa, minutissima, prae- 

 dita locomobilitate plusminusve manifesta ; inter se ab uno extremo ad 

 alterius extremum ordine longo cohserentia, sive in statu primordiali, 

 sive post elongationem plus minusve notabilem ; efformantia hac ad- 

 junctione fila inertia, hyalina, creberrima, ramosa, moniliformia, vel 

 dissepimentis conspicua, fere semper incumbentia liquoribus, vel sub- 

 stantiis humidis in quibus nascuntur et ubi, per eorum implicationem, 

 constituunt pelliculam plus minusve spissam. Generatio per gemmas 

 interiores." 



The resemblance in figure, however, of this parasite to various 

 growths, in all probability vegetable, is equally striking, if we do not 

 consider that all growths composed of distinct rounded cells, whether 

 of animal or vegetable nature, will necessarily much resemble each 

 other. For instances of this resemblance, it is only necessary to refer 

 generally to the plates in M. Corda's work.f and particularly to the 

 figures of Gonatorhodon speciosa ; the extreme filaments of Stysanus 



* " Recherches Microscopiques et Physiologiques sur le genus Mycoderme." 

 Annales des Sciences Naturelles,/Tom. X. l e . Ser. 1826. 



t Pracht- Flora Europaeischer Schimmelbildungen, Leipzig, 1839. 



