﻿4° SMITHSONIAN MISCELLANEOUS COLLECTIONS [VOL. 47 



( Ihio, which he had previously described as a species of Callopora. 

 As the internal characters of the genotype have not been figured, 

 we make use of this opportunity to publish illustrations (plate xn, 

 6-9) of thin sections prepared from authentic examples. The rela- 

 tions of the genus are with Lioclema, and it would be difficult to 

 point out satisfactory differences in their internal characters. How- 

 ever, the zoarial habit of growth of Lioclcmella, consisting of club- 

 shaped or sparsely divided branches, pointed at the proximal ex- 

 tremity for articulation with an attached, expanded base, is deemed 

 of sufficient importance to justify the recognition of the group gener- 

 ically. 



Besides the species listed in Nickles and Bassler's Synopsis of 

 American Fossil Bryozoa, the genus will contain at least several 

 other good species from the Richmond formation of Ohio and the 

 Rochester shales of New York. 



Division II. — IXTEGRATA new division 



Trepostomata in which the boundaries of adjacent zocecia are 

 sharply defined by a black divisional line. 



Family AMPLEXOPORID^E Ulrich 



This family includes the most simple types of the Integrata. On 

 account of this simplicity and the practical absence of mesopores, 

 they also show the duplex character of the wall which separates 

 adjoining zocecia and upon which this division is founded, in a more 

 satisfactory manner than the other families. The black divisional line 

 is always in evidence, while in the Calloporidce and Trematoporidce 

 it is generally obscured by the interposed mesopores and is certainly 

 demonstrable only in those occasional species in which the develop- 

 ment of mesopores has been reduced to a minimum. 



The removal of Leptotrypa and Atactopora to the Heterotrypidce 

 has materially affected the status of the AmplexoporidcB. Possibly 

 it would be wise to replace these genera, in part at least, by the recog- 

 nition of a genus for such permanent integrate Leptotrypas as L. 

 discoidea (Nicholson). The genotype of Eichwald's genus Orbi- 

 pora, 0. distincta, as worked out by Dybowski, 1 seems to belong to 

 this group and future research may show Orbipora to be the proper 

 genus for the reception of /.. discoidea. 



The new genus Rhombotrypa has been long in contemplation, and 



1 'hcetetiden der OstbaltiscJicn Silur.-Form., p. 57. 



