50 DlCTYOSPONOID^ 



morpliology of the sponges, both of their soft and skeletal parts, with abun- 

 dant illustration, is constructed with especial reference to the fossil forms. In 

 the systematic treatment of these bodies the suborder Lyssacina is made to 

 include eight families, as follows : Protospongid^, Hinde, DictyospongiduE, 



Hall, PLKCTOSPOXCilDyE, Rauff, EuPLECTELLIDyE, Gray, ASCONEMATID^E, SchulzC, 



RossELLiD.E, Schulze, HYALONEMATiDyE, Scliulze, Bbachiospongidye, Beeclier. 



The author is the fli'st to establish distinctive characters between the 

 Protospongid^ and the Dictyospongid^ and to suggest the probability that 

 Cyathophycus, Plectoderma and Piiormosella are not safely placed with 

 either of these families ; hence the erection of the family Plectospongid^. 

 The final chapter in this portion of the work relates to the mode of preserva 

 tion of the fossil sponges. 



1894. 



37. Hermann Rauff. Palaeospongiohgie, Part 1, Liefermigen 5, 6, pp. 233— 

 . 3^.6, ph. i-xvii. (Palaeontographica, vol. xl.) 



This instalment of the same work is devoted to descriptions of palaeozoic 

 species. The various forms of the Protospongid^ described by Dawson, and 

 the Plectospongid^e (Cyatiiopiixcus, Teganium), are described and in many 

 instances illustrated with new figures. On page 249, under the family 

 DicTYOspoNGiD^, is described as Didyopliytra (.^) Walcotti, Rauff, a new 

 species from the Utica slate at Holland Patent, N. Y. Dictyopuytka is evi- 

 dently a proposed modification of the term Dictyophyton ; as a substitute for 

 the latter it is imobjectionable etymologically and in its application to these 

 fossils, but it is objectionable historically if xised in the broad sense in which 

 the term Dictyophyton has heretofore been applied. The definition of the 

 genus is deferred to a later part of the work and its value, therefore, can 

 not be determined xuitil the author makes known upon what forms of 

 " Dictyophyton " the genus is based. 



Dictyophytra (?) Walcotti, (pi. iv, figs. 1, 2) is founded upon the frag- 

 ment of a large, coarse-meshed species, quite distinct in size and texture from 

 its associate, Gyatli&phyaus feticulatus. That it is a true Dictyosponge, how- 

 ever, and not a Cyathophycus, can not be regarded as established. 



The 7th and 8th Lieferungen of this work, dated 1895, contain nothing 

 especially relating to the Hexactinellida. 



We gi'eatly regret that Dr. Rauff's observations upon the Devonian and 

 Carboniferous Dictyosponges have not been received as this volume goes to 

 press. 



