594 Canon A. M. Novman — Notes on the 



rounded corners there grow out nodulous processes^ some- 

 times of very considerable size, and the sliglit central hollow 

 is filled up ; the structure now assumes the form of fig. 2 c. 

 When this nodulous growth is fully developed the zoainum 

 has a very peculiar appearance, and reminds us somewhat of 

 C. aurita, for the lateral avicularia of the two alternating^ 

 zocecia above nearly meet, and rarely actually coalesce with 

 the nodulous interzooecial growth which has been described. 

 The foregoing would appear to be a peculiar form of ooecium 

 and it is that which is tlie common one found in the species. 

 Very rarely, so far as my observations go, the form of a 

 shallow cap is taken on (fig. 2«), and this is the ooecium, which 

 Hincks figured from the Charlotte Isles, On one portion 

 of my specimen from the ' Vega '' Expedition a very different 

 form of ooecium is found (fig. 1 c) : I have seen it only on 

 zocecia in which the usual lateral avicularia are absent. The 

 form taken reminds one of a " fool's cap,^^ the front rim of 

 which is well rounded ; from this the ooecium narrows 

 gradually, and at the same time is also more depressed, 

 imtil it ends in a nodulous process. There are perhaps 

 twenty such ooecia together, though there is considerable 

 variation in their exact length ; close to them are, on other 

 zocecia, ooecia of the ordinary form (fig. 2 b). 



This is a very large species, which grows most luxuriantly 

 and is generally only loosely attached to the object on which 

 it is developed. It is of a rich deep brown colour, Hincks 

 says " deep black, ^' but, notwithstanding that statement, he 

 has given it a very expressive specific name in " nhp'cms." I 

 have compared my specimens with the type of Hincks, from 

 the Charlotte Islands, which is now in the British Museum ; 

 and the ' Vega ' locality, which I shall presently give, 

 aflbrds additional evidence that it is a circumpolar form. 



It may be the lleptofliistrina americana of d^Orbigny. 

 Smitt refers to that species, which was found at Newfound- 

 land, and he also states that the species from Labrador 

 which Packard recorded under the name " "^ Lacroixii,'" but 

 Avithout any description, was, from specimens sent to him by 

 that writer, identical with what he calls ^' forma americana.'* 

 It must remain in some doubt to which of two forms Smitt 

 in that statement refers, for Avhile his fig. 31 with its large 

 avicularia on the ovicells undoubtedly represents what I have 

 here described as G. unicornis, var. armifera, specimens 

 which he kindly sent to me named "forma americana " are 

 as undotibtedly that which I here refer to C. nigrans, Ilincks, 

 which, among other marked characters, never has large 

 avicularia on the occcia. 



