PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 193 



ooecia are prominent, but scarcely globose, the front surface being more 

 or less flattened, and perforated with rather large pores, which are 

 mostly confined to the flattened front surface. The median avicularium 

 is well-rounded, direct, and just in front of the well-defined sinus. This 

 species occurs in the encrusting (Lepralian) form, and also in the various 

 foliaceous (Hemescharine) states, sometimes cup-shaped, saucer-shaped, 

 and hat-shaped, according to place of growth. It is very common in the 

 Bay of Fuudy and on the Grand Banks. 



Escharina Edw., 1835, = HippofIwa (jjars) Smitt, = ScMzojm-cIla Hincks, 1879. 



Edwards, in estabhshing this generic group, assigned a definite spe- 

 cies as its type {U. vulgaris Moll) ; and although he afterwards united 

 with it several incongruous species, the name ought to be retained for the 

 group including his specified type. The earlier name, Rippothoa Lamo- 

 roux, adopted by Smitt for this group and the true Hippothoa, combined 

 with it by him, should, of course, be retained for the group typified by H. 

 divaricata, from which R. lujaUna (type of CcUeporcUa Gray) does not 

 appear to me to be generically distinct. The name given by Edwards, 

 being next in order,* and definitely applied, should, therefore, be retained 

 for the present group. JMoreover, Gray, in 1848, when restricting the 

 genus, retained the name for the typical group. The name Rerentia 

 Gray, as restricted by Smitt, would also be available for this group, if 

 Uscharina could properly be rejected. In any case, the new name pro- 

 I)Osed by Hincks seems wholly unnecessary. 



Escliarina, as understood by me, includes those species which have 

 the primary zooecial aperture more or less subcircular, with a distinct, 

 often narrow, median sinus, and with the avicularia lateral, when devel- 

 oped. Mode of growth various, but more generally encrusting in a sin- 

 gle layer; sometimes, as in E. Isabelliana, forming thick masses, consist- 

 ing of numerous layers of cells. Our species, so far as determined, are^ 

 as follows: 



Escharina IsahelUana D'Orb. = ^. variabilis Leidy. 



Escharina reversa Verrill. Perhaps a variety of the preceding. 



Escharina linearis (Hassal). 



Escharina hiaperta (Mich.). 



Escharina secundaria (Smitt). 



Escharina ansata (Johnst.) Gray. 



Escharina porosa Verrill, sp. nov. 



One or two undetermined species are also in our collection. 



Escharina porosa Verrill, sp. nov. 



Escharella 2)ertusa Yerril[, Amer. Journ. Sci., vol. x, p. 41, 1875, (non Smitt). 

 Zoarium encrusting sheUs and stones. Zooecia large, oblong, perfo- 

 rated by numerous, rather large, round pores ; apertures large, roundish, 



* The name Escharina was used by Ehreuberg in 1834 as the name of the family, but 

 in that sense-it was a synonym of Escharidw Fleming, 1828, and consequently might be 

 used as a generic name in another sense. 



Proc. iTat. Mus. 79 13 Nov. 5,18 79. 



