SPONGES FEOM THE WESTERN COAST OF NORTH AMERICA. 115 



There are, besides, a number of specimens of a rugose form' that not only have a sur- 

 face made irregular, in the most typical specimens, by the development of numerous short 

 protuberances hut are also characterized by having somewhat larger spicules. The largest 

 oxea, in different specimens, vary in length from 1-096 to 0-685 mm. 



Distribution. — Arctic Ocean, Behring Sea and N'orth Pacific Ocean. 



EuMASTiA SITIENS, 0. Schmidt. 



Eumaslia giliens, O. Schmidt. 1870. Grundz. einer Spong.— Fauna des Atl. Geb., p. 42, pi. v. ; fig. 1-2. 



" " Fristedt. 1887. Sponges from the Atlantic and Arctic Oceans and the Behring Sea, (translation), 



Veera-expeditionens vetenskapliga arbeten, p. 426, pi. 24, fig. 13, and pi. 27, fig. II. 



This species is represented by over a dozen specimens, some of which are of considerable 

 size ; one a particularly tine specimen is about 150 mm. in length, 90 mm. in breadth and 75 

 mm. high, its fistulœ reach a length of 30 mm. with a basal breadth frequently of 9 mm. 

 The fistular processes are so delicate and brittle when dr^', that, unless the sponge be 

 preserved in alcohol, they are difficult to preserve intact. 



The oxea vary considerably in length in the same individual ; the greatest length 

 attained in the specimens under consideration is 1-15 mm. 



Distribution. — Behring Sea and North Pacific Ocean. 



Petrosia hispida, Ridley and Dendy. 

 (Plate IL, Fig. 1.) 



Petrosia hispida, Ridley and Denily. 1886. Ann. and Mag. Nat. Hist., series 5, vol. xviii., p 327. 



" " Ridley and Dendy. 1887. Rep. Monaxonida, Zool. Chall. Exp., vol. xx., p. 14, pi. ii., fig. 16 j pi. 



iii., fig. 2. 



This species is represented by a small sessile specimen, 40 mm. long, 22 mm. broad and 



16 mm. high, of a rich brownish-yellow colour in alcohol, and with numerous circular oscula 



about 1-5 mm. in average diameter, as in the type specimens. There is also in the collection 



a fragment of another specimen from the same locality. 



The oxea (Plate II., fig. 1) vary in size from 0-327 by 0-026 mm. to 0-242 by 0-016 mm. 

 Locality. — Middleton Island. 



Reniera rufescens, Lambe. 



Reniera rufescens, Lambe. 1892. Trans. Royal Soc. Canada, vol. x., p 75, pi. iv., fig. 6, pi. v., figs. 12, 12a. 



A number of specimens referable to this species are represented in this collection ; from 

 them it is seen that the sponge is sometimes arborescent, though still retaining the peculiar 

 lobate manner of growth of the specimens originally described ; the branches frequently 

 coalesce and usually terminate in somewhat knobbed extremities. A few specimens approach 

 more nearly in outward form to the type specimens. 



The oxeote spicules attain a maximum length in different specimens of from 0-157 to 

 0-216 mm., with an average breadth of 0-013 mm. 



Distribution. — Arctic Ocean, Behring Sea and North Pacific Ocean. 



Toxochalina borealis. (Sp. nov.) 

 (Plate II., figs. 2, 2a— e.) 



Sponge (Plate II., fig. 2) sessile, forming irregularly shaped thickly incrusting masses. 

 Colour, in spirit, a dull yellowish-brown. Texture rather soft, spongy. Surface mammate, 



' Sponges from the Pacific Coast of Canada and Behring Sea, Trans- Royal Soc. Canada, 1892, vol. x., p- 75, pi. 

 iv., fig. 3, pi. v., figs. 9, 9a. 



