260 THE AMERICAN MONTHLY [November, 



of entangled hair. Many such hairs or parts of hairs seem to be a 

 solid mass of fungus spores. 



In size the spores average, when in chains, as they are usually to be 

 found in the hair, 3.5 micromm. ; the filaments average about 3 mi- 

 cromm. in width. The filaments may show scattered granules, but 

 vacuoles are not seen, and branching is not very frequent. Short, 

 abortive branchlets are not uncommon. The size of the fungus ele- 

 ments (spores and mycelial threads) does not appreciably vary in cat- 

 tle and horses. 



In human pathology this parasite, by its growth in the skin, gives 

 rise to various forms of disease, all included under the common desig- 

 nation of *' ringworm," the ditierences being due to the various posi- 

 tions in which the parasite is found. The affection in young cattle 

 corresponds to ringworm of the scalp in children {llnea tonsui'ans) ^ 

 and the fungus thus described seems to be identical with the Tricho- 

 phytoti tonsiirans. 



Botanists have, for the most part, been reluctant to recognize this 

 fungus otherwise than as a modification of some common mould; but 

 the researches of Grawitz, Quincke, and others by aid of modern bacte- 

 riological methods seem to prove it a distinct species. It is placed 

 with the Odium lactis^ intermediate between the true moulds and the 

 sprouting fungi or yeasts. Grawitz has shown that it is the immediate 

 cause of ringworm. However, there is always very manifestly, in 

 cattle at least, a certain condition of the skin necessary for its growth. 



In testing the contagiousness of bovine form of ringworm, it was 

 found that scales taken from a diseased patch and rubbed dry on another 

 animal, or on another part of the same animal, seldom produced infec- 

 tion. If, on the other hand, the infectious material was well soaked in 

 water, and then applied, the disease was almost certainly reproduced, 

 and it was not necessary to cut or abrade the surface where the spores 

 were applied. This was in winter and early spring. Later, when the 

 cattle obtained an abundant supply of good pasture, it was impossible 

 to produce artificial infection, and animals already infected recovered 

 spontaneously, with complete return of hair, and without any trace of 

 the disease remaining. No doubt the vernal shedding of the hair largely 

 contributes to the removal of the fungus from the skin. 



Action of Cold on the Virus of Rabies. — A rabbit which had 

 died of rabies was immediately placed in a chamber, the temperature of 

 which ranged from 10° to 37° below zero C. After having been frozen 

 for six months, the spinal marrow of the animal was removed, and 

 inoculations from it were made upon a healthy rabbit. After two weeks 

 time, the inoculated animal presented symptoms of hydrophobia and 

 died two days later. — Le Bull. Med. 



Cycle of Taenia Coronula. — In the Iittemat. Jour. Micros, d- 

 Nat. Sci. for October, 1891, T. B. Rosseter records observations that 

 seem to determine the life cycle of Tcenia corotzula., Dujardin. The 

 host of the adult tape-worm is the duck. The ripe proglottides, being 

 expelled from the duck, burst and set free the eggs, which develop into 

 minute worms. These, entering within the shell of Cypris cinerea^ be- 

 come encysted, and develop into what has been known as the Cysti- 

 cercus of Cypris cinerea. The duck swallows the Cypris, and within 

 the viscera of the duck the Cysticercih^covao. mature tape-worms. 



