7^ 



THE AMERICAN MONTHLY 



[April, 



The peculiar branching hairs are very 

 curious. 



The second slide is a section of 

 fossil coral having walls of calcile — 

 crystalline carbonate of lime — with 

 quartz-crystals lining the chambers. 

 The section is very instructive, and 

 in polarized light is very beautiful. 

 Mr. J. D. Hyatt, who contributes 

 this slide, described the structure of 

 the coral and the process of crystalliza- 

 tion within it at a meeting of the New 

 York Microscopical Society, not long 

 ago, as will be seen by referring to the 

 notices of the meeting already pub- 

 lished in this Journal. 



Mr. G. I. Whitehead contributes the 

 third slide, which contains a crustacean 

 from a surface-dredging in the Indian 

 ocean. A characteristic of this — as 

 well as of all the other animals found 

 in the dredgings — is the large, pro- 

 truding eyes. 



On the arrival of this box we were 

 pleased to find the slide of Spirogyra 

 which we contributed long ago — it 

 must be two years ago if our memory 

 serves us right. It was mounted in 

 fluid, and comes back to us after a 

 varied experience in mail-bags and in 

 different climes, just as perfect as 

 when it left our hands. Yet micro- 

 scopists complain that mounts in fluid 

 are not durable ! 



Our own contribution to this box is 

 a beautiful species of CEdogonium — 

 CEdogonitim Boscii in fruit, showing the 

 oogonia with the oospores. This also 

 is a mount in water, and we trust it 

 will complete its journey as safely as 

 its predecessor. 



British Fresh -Water Alg^. — 

 The fourth part of this work by 

 Mr. M. C. Cooke has reached us. It 

 embraces the families, Vaucheriaces, 

 Ulvaces and Confervacese. The au- 

 thor treats his subjects well, with quo- 

 tations from the latest authorities 

 which cover the observations on the 

 life-history of the plants. Of species 

 of Vaiuheria he has a variety of forms, 

 bat we question the distinctness of 



several, particularly the two species 

 V. hamata, and V. terrestris. The 

 claims made for the distinguishing 

 features of the two forms we find oc- 

 curring in common. V. tuberosa, A. 

 Br., of which we have three varieties, 

 does not appear to be a British plant. 

 V. soricea, should be scricea, a species 

 we have not recognized here. 



Prasiola is a genus of distinct 

 forms ; we have been able to trace 

 only two species in this country : P. 

 crispa, and P. Mexicana, Liebm., 

 the latter a larger form collected 

 from rocks in a high mountain stream 

 of Colorado. 



Sphceroplea is finely illustrated ; 

 hitherto this plant has not been found 

 in the United States. 



Among the Confervaceae, we con- 

 sider the genus Alicrospora of no suffi- 

 cient valye to retain the position 

 given it by Thuret. In this connec- 

 tion the author quotes the name of 

 Dr. Kirchner six times but incor- 

 rectly with an s — " Kirschner." We 

 think it would have been wisdom to 

 adopt the Doctor's ruling throughout. 



Enteromorpha and Chcetomorpha are 

 marine or submarine plants. 



Rhizocloniums do not appear w^ell 

 represented in Great Britain. The 

 cladophoras also, are more numerous 

 with us ; finally, Pithophora, which 

 seems to have been introduced from 

 tropical climes into the Kew Gardens 

 of London, has a home in the States 

 of Florida, New Jersey, and Pennsyl- 

 vania. F. W. 



NOTES. 



— Prof. Koch's experiments on disin- 

 fectants show that the most efficient are 

 chlorine, bromine, and corrosive subli- 

 mate. A solution containing one part of 

 the latter in loooof water will kill fungus- 

 spores in a few moments, and a much 

 weaker solution will cause total arrest of 

 development. 



— The second volume of Cole's " Studies 

 in Microscopical Science," promises to be 



