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SCIENCE 



[N. S. Vol. L. No. 1288 



Classification on tlie basis of form has now 

 given way to classification on the basis of the 

 skeletal elements, a method adopted for recent 

 sponges by Schulze in 1875, and for fossil 

 forms by Zittel in 1876. 



In this chapter Dr. O'Connell gives a review 

 of the work done on fossil sponges to date in 

 Great Britain, France, Eussia, Bohemia and 

 Germany. Based upon the summaries given 

 by Eauff (Palseontographica, 1893-94) the au- 

 thor has brought the review up to date, and 

 given us moreover a critical evaluation of all 

 the important works which she has been able 

 to examine personally, so that the student, 

 especially the one not conversant with German, 

 will find this the most satisfactory general his- 

 torical summary in print. It is true that a 

 few important papers have been overlooked, 

 among them Siemiradski's monograph, " Die 

 Spongien der Polnischen Juraformation " 

 (" Beitrage zur Palseontologie und Geologic 

 Osterreich-Ungarns und des Orients," Bd. 

 XXVI., pp. 163-211, 1913, and in the Polish 

 language in the publications of the Scientific 

 Society of Warsaw for the same year), in 

 which 92 species including a number of new 

 ones are described according to modern meth- 

 ods, and illustrated on six quarto pages, and 

 Vinassa P. de Eegny's " Trias-Spongien aus 

 dem Bakony" (" Eesultate der wisseiischaft- 

 lichen Erforschung des Balatonsees," Bd. I., 

 1901) and " Neue Schwamme, Tabulaten und 

 Hydrozoen aus dem Bakony" (ibid-, 1908), 

 but as the author's work was primarily with 

 the Cretaceous sponges, such an oversight is 

 not to be wondered at. 



Chapter II. deals with the morphological 

 characters of the Silicispongiae, and this chap- 

 ter is of value because it gives to the student 

 the only comprehensive account of the char- 

 acters and classification of the skeletal ele- 

 ments to be found in the English language 

 not excepting that of Hinde. It is a more 

 systematic presentation, because arranged 

 chiefly in tabular form, than the elaborate one 

 given by Eauff, and on that account will be 

 found more serviceable to the general stu- 

 dent. It is also more complete than that of 

 Eauff, because it includes a nurnber of new 



types introduced by Schranimen, and renders 

 moreover into English a number of terms so 

 far only used in German literature. This 

 chapter is illustrated by 14 plates of outline 

 drawings, selected from the illustrations given 

 by Eauff and Schrammen. By an oversight 

 these are all credited to Schrammen oh page 

 34, though 48 out of the total of 71 are from 

 Eauff, as correctly given in the description of 

 plates. Plates I.-V. give an illustration for 

 each type of spicule, while on Plates VI.-XIV. 

 are given illustrations of the actual spicules of 

 the species represented in the American 

 Museum collection. The relationships of the 

 many special types of spicules to, and their 

 derivation from the three fundamental types 

 the triod, tetraxon and the triaxon are also 

 clearly set forth. In the discussion of the 

 microscleres, reference should have been made 

 to the important, though preliminary paper 

 by P. Ortman, " Die Mikroscleren der Kiesel- 

 spongien in Schwammgesteinen der Senonen 

 Kreide " (" ISTeues Jahrbuch fiir Mineralogie," 

 etc., 1912. Bd. II., pp. 127-149). 



Chapter III. presents in 50 pages a sum- 

 mary of the stratigraphy of the Upper Cre- 

 taceous formations of Europe, and is in many 

 respects the most valuable part of the work. 

 Here the student will find what is probably 

 the best general summary of this subject in 

 the English language and the reviewer would 

 j-ecommend the perusal of this chapter to all 

 students of European stratigraphy. It is not 

 merely a summary of text-book literature, but 

 is evidently based on a study of the original 

 works, and reveals the author's grasp of the 

 fundamental principles of stratigraphy. The 

 study of the Cretaceous stratigraphy of Eu- 

 rope was undertaken by Miss O'Connell, as 

 she tells us in the preface, as a part of the 

 research work under the Sarah Berliner Ee- 

 search Fellowship for Women which she held 

 for the year 1917-1918, and which was a study 

 of the " Habitat of the Silicispongise." In 

 this discussion of the stratigraphy the field is 

 divided into eleven provinces, the disconnected 

 character of which is primarily the result of 

 post-Cretaceous erosion, which in many areas 

 has removed the transitional facies of the 



