230 VEGETABLE PAKASITES. 



colour the favus- or tinea-mass, was interpolated. The fungous 

 mass, which sometimes appeared of a reddish-gray hue, invariably 

 occurred far back, between the foliated masses, near the edge of 

 the lunula, in large lenticular heaps. Virchow believes that 

 the fungus is equally important to the disease of the nails just 

 described as to Porrigo and Pityriasis versicolor ; but not so to 

 the Gryphosis of the nails by itself, for many more intense diseases 

 are frequently unaccompanied by fungi. 



I am only following Virchow in classifying this fungus in the 

 mean time with Aspergillus, reserving for myself, however, in case 

 I should be able to collect further information, the right to give 

 it another place. Meissner' s illustration of it would most likely 

 classify it with Achorion Schoenleinii ; and Virchow likewise 

 points out that it forms a mass resembling very much the favus- 

 mass. But Achorion is without articulation, which Meissner and 

 Virchow state they have distinctly seen. Next to Achorion 

 Meissner's illustration resembles the Oidium albicans. The en- 

 tanglement of the filaments forms a kind of network, and their 

 articulation is likewise in favour of this theory, the only objection 

 being its different seat. According to what has been said at the 

 end of the division, " On the circumstances favorable for the deve- 

 lopment of the fungus" when speaking of Oidium albicans, it might 

 be thought possible that it should also occur in the deeper layers 

 of the nail-bed, i. e., on the numberless young nail-cells analogous 

 to the epithelium. I, for my part, am not disinclined to think 

 that this nail-fungus is related to Achorion or Oidium, and to 

 leave the proof of this doubtful point to some one more expe- 

 rienced. The nail-fungus found a place here because I should 

 not like to contradict recognised authorities, resting on a mere 

 " opinor," and I may be permitted to quote what Gudden has 

 said of Achorion : " Similar favorable conditions as the little 

 hair-funnel offers to the reception of fungous particles would be 

 offered by the furrow leading to the bed of the nail, if the fre- 

 quent washing of the hands did not counteract it." Also the 

 quotation of Gudden, from Canstatt's ' Hand-book of Med. 

 Clinics/ 3d edit., p. 1092 : " The horny mass of the nails suffers 

 likewise when the extremities are attacked by porrigo. The nails 

 become disfigured, they crack, and fall off." 



Literature. Meissner, in Vierordt's 'Archiv/ 1853, xii, 

 p. 193, with tab. i; Virchow, in ' Verhandlungen der physikal 

 med. Gesellschaft zu Wiirzburg/ v, 1, 1854, p. 102. 



