Reviews — Cretaceous Crabs from S. Dakota. 225 



Caribbean species. Each of the known species is described and 

 compared with allied forms. The editor lays great stress on the 

 illustrations. One or more specimens of each species have • been 

 photographed so as to bring out the diagnostic character^ and 

 Dr. Sheldon has spent two years in obtaining photographs which 

 could be reproduced without retouching. These, as well as Jgfcfato- 

 graphs of drawings previously published by Dall and other^^Rive 

 been mounted on a background apparently of dark American cloth, 

 and reproduced in half-tone as quarto plates. Professor Harris holds 

 that such plates are " practically as good as museum specimens for 

 critical study ", and that the publication of works of this character 

 will therefore enable satisfactory investigation to be conducted in 

 remote institutions. Experience alone can decide whether the 

 photographs will bear out this enthusiastic claim. At present we 

 can only say that, while the general effect is pleasing and most of 

 the photographs very good, still the clearest illustrations on each 

 plate are the reproduced drawings, and the outline of some of the 

 more shaded and rounded specimens is far from distinct in the 

 photographs. But, granting the contention of Professor Harris, we 

 are all the more surprised that he should have thought it advisable 

 to reproduce such fine plates on "art" paper, and to issue a work 

 of such importance with the sheets transfixed by wire instead of being 

 stitched. "Time only can tell," he says, whether the experiment 

 will prove a success. In a fight with time it is unwise to handicap 

 oneself by using perishable materials. The subscription rate is 

 2 cents per page and 10 cents per plate. Hence No. 1 may be had 

 for $3.60 (15 shillings). 



XII. — Cretaceous Crabs from S. Dakota. — Some crabs from the 

 Pierre Shales are described by Miss Mary J. llathbun (Feb. 1917, 

 Proc. U.S. Nat. Mus., vol. 52, pp. 385-391, pis. 32, 33). One, 

 called after the discoverer, Dakoticancer overana [why feminine ?], 

 gives rise to a new superfamily of Dromiacea, the Dahoticancroideae [jjj, 

 at least three notes of abhorrence are needed for this mass of 

 barbarisms], since the absence of longitudinal grooves from the 

 sternum of the female removes it from the Dromioideae, while the 

 sheltering orbits and the absence of lineae anomuricae distinguish it 

 from the Homoloideae. " There is no complete specimen even of the 

 carapace," but, though the description is completed, no reconstructed 

 figure is attempted. A. new species each of Homolopsis and 

 Campylostoma are also described with care from a few imperfect 

 specimens. 



XIII. — The Flora op the Fox Hills Sandstone. By F. H. Knowlton. 

 U.S.A. Geological Survey, Prof. Paper 98-H, pp. 85-93, 

 pis. xv-xviii. 1916. 



rpHE marine formation of the Fox Hills Sandstone has hitherto 



JL yielded very few plant fossils, though it lies between two 



Upper Cretaceous deposits which are abundantly provided with plants. 



The present paper gives a list and descriptions of twelve vascular 



DECADE VI. — VOL. IV. — NO. V. 15 



