388 



SCIENCE. 



[X. S. Vol. XXI. Xo. 532. 



photo-synthesis and the iissimihitiou of nitrog- 

 enous substances. This is to be regi'etted, 

 for it fails to bring out the essential differ- 

 ences between these forms of chemical activity 

 within the plant. This is especially true since 

 the author follows the fate of the nitrogenous 

 products up to the point of the final construc- 

 tion of albuminous material and even con- 

 siders the processes of digestion before a word 

 has been said about respiration and the ac- 

 companying phenomena. It is true that in 

 the following section, on dissimilation, as the 

 author terms it, the phenomena connected 

 with respiration are spoken of from the stand- 

 point of the release of kinetic energy, but the 

 importance of this in the upbuilding processes 

 in nitrogen assimilation is not sharply brought 

 out. The first part, on nutrition, closes with 

 a cleverly constructed diagram which brings 

 out the origin and fate of the various sub- 

 stances connected with nutrition processes. 



In the already noted division of the balance 

 of the book into two parts, it is not altogether 

 evident that there is much advantage over the 

 more usual plan. The problems connected 

 with the change in form, in short the growth 

 of the plant, are in many ways intimately con- 

 nected with growth curvatures, yet in the 

 arrangement followed the former are included 

 under ' Formwechsel,' the latter under ' En- 

 ergiewechsel.' If this treatment tends to draw 

 the attention of the student from the relation 

 of expenditure of energy to ordinary growth 

 phenomena, or if thereby growth curva- 

 tures — tropism — are separated too sharply 

 from unmodified growth responses, it seems to 

 hinder rather than help the proper apprecia- 

 tion of the question as a whole. Some sub- 

 division is certainly an advantage, but it 

 might have been better if the title ' Energie- 

 wechsel ' had been used for both of the sec- 

 tions and suitable subtitles devised to indicate 

 more adequately the different phenomena. 



Aside from such points, which are, perhaps, 

 after all, but matters of opinion, there can be 

 no question but that the book is an excellent 

 one. It is clear, concise, fairly up to date as 

 regards the literature, and, moreover, written 

 in a style which makes it attractive and inter- 

 esting reading. One can but regret that there 



is not a book in the English language so suit- 

 able for the student; it is to be hoped that a 

 translation will appear. 



Columbia. U.niveksity. H. M. Eichards. 



Cleiocrinus. By Frank Springer. Memoirs 



Mus. Comp. Zoology, Harvard College, Vol. 



XXV., No. 2, January, 1905. 



A few years ago the Museum of Compara- 

 tive Zoology brought out Mr. Springer's beau- 

 tiful and exhaustive account of Uintacrinus, 

 and now we have before us a similarly com- 

 plete paper on one of the oldest of known 

 Crinoid genera — Cleiocrinus. This genus was 

 described by E. Billings in 1856, from speci- 

 mens found in the Lower Silurian at Ottawa, 

 Canada. It has been discussed by various 

 authors, who have had great difficulty in 

 placing it in the system of classification, 

 owing partly to its anomalous character, and 

 partly to the condition of the specimens. In 

 1886 Messrs. Wachsmuth and Springer wrote: 

 ' If certain parts were better known, we 

 should make it the type of a new family, but 

 at present, having no positive knowledge of 

 the basal regions, nor even of the arms, we 

 are not in a position to give a satisfactory 

 definition of the group.' Mr. Springer does 

 not now establish the family Cleiocrinidae, in 

 so many words, but it is evident that the ex- 

 pectations of 1886 have been more than real- 

 ized. The story of the discovery of the new 

 characters is so dramatic that it is worth 

 quoting nearly in full : 



It was apparent, however, that no further in- 

 formation was to be obtained, unless we could 

 find some means of seeing what is underneath the 

 cohimn. My examination of the specimens gave 

 no hope of being able to detach the column in 

 either of them; but after a very careful study 

 of specimen B [one of Billings's types borrowed 

 from the Geological Survey of Canada], under a 

 strong magnifier, I came to the conclusion that 

 it miglit be possible to get at the inside of the 

 base by removing a part of the plates above it. 

 * * * * The small size of the specimen and 

 the uncertainty as to how the fractures might run, 

 rendered the operation a delicate and risky one 

 to undertake with a type specimen; but I thought 

 tlie benefit to be gained in case of success would 

 warrant the risk. I accordingly laid the matter 

 fully before Dr. AMiiteaves, and requested his 



