Polyzoa of the St. Lcaorence. 1/5 1 



Eschara jxilmata of Sars seems to be referable to tlic same 

 form *. 



On a consideration of the whole question I can only suggest 

 that probably we have to do with one of the species in which 

 the orifice of tiic cells bearing the ooecium differs in structure 

 from that of the ordinary cells. The larger specimens both 

 from Barents Sea and the St. Lawrence were thickly covered 

 with ooecia, and on these I have been unable to find an 

 example of the orifice with the central sinus. On specimens 

 of the smaller form from the St. Lawrence the latter was 

 universally present. At the same time it must be admitted 

 that the exclusive presence of one form of cell througliout 

 fine and well-develo])ed colonies affords a presumption against 

 the explanation which 1 suggest. In similar cases the two 

 classes of cell are always, so far as I know, mingled together. 

 The alternative view would be that these forms are distinct 

 species, which seems to be highly improbable. 



Opinions have differed widely as to the precise systematic 

 position of Flustra solida. Stimpson, who first described it, 

 referred it to Flustra, to which it bears a certain amount of 

 superficial resemblance ; but there is no real affinity between 

 the two. Sars ranked it in the old genus Eschara, simply on 

 the ground of its zoarial habit, whilst Verrill placed it in the 

 Flustramorjyha of Gray, a genus since adopted by Busk for 

 forms with a Mieroporellidan cell and an erect mode of 

 growth. Such a genus can of course find no place in our 

 later systems of classification f. 



Smitt has discussed the affinities of this species in the light 

 of the new views of which he has been so able an expositor, 

 and assigns it a place in his genus Escharella, which (as 

 finally limited) is identical with Smittia \. Undoubtedly 

 there are points in which it agrees with the members of this 

 genus, though the differences are by no means unimportant. 



The orifice in such a species as Smittia reticulata before the 

 development of the peristome bears the closest resemblance 

 to that of Flustra solida in its larger form, the presence of a 

 central denticle and of marginal spines being the only points 

 of difference §. But Prof. Smitt had not met with the other 

 form of orifice carrying a sinus on the lower margin, which 



* lu Stimpson's figure the aviculavium is represented as small aad 

 suborbicular. 



t Verrill makes the presence of " chitiuous fibres strentrthening the 

 zoarium " the distinctive generic character. Bat this is common to many 

 ■\ ery dis.-imilar forms. 



t ' British Marine Polyzoa,' vol. i. p. 341. 



§ * History of British Marine Polyzoa,' pi. xlviii. fig. 4. 



