278 



The Ottawa Naturalist. 



March 



One specimen of each of the remainhig species Siiherites mont- 

 albidus and Craniella craniuvi was dredged by Mr. Low in June, 

 1899, '" Richmond Gulf, Hudson Bay, in from 15 to 30 fathoms, 

 soft mud bottom. 



Snberites montalbidus has a wide northern distribution and it 

 is not surprising- to find it in Hudson Bay. Its range includes 

 Behring Sea and Strait, Beaufort Sea, the Siberian Arctic Ocean, 

 the Kara Sea, the European Arctic Ocean, Barem's Sea, and the 

 sea west from Greenland (vide Transactions, Royal Society of 

 Canada, vol. xii, 1894). The Hudson B ly specimen is irregularly 

 pear-shaped, higher than broad, broader above than below where 

 it has apparently been attached to some hard object ; height 6 

 cent., greatest breadth a little over 4 cenjt., colour in alcohol a 

 dark grayish brown, surface rough (except on the top, where it 

 is comparatively smooth), covered with small, irregular elevations 

 separated from each other by a net-work of wrinkles or furrows. 

 A single osculum, about 8 mm. in width, occupies the centre of 

 the summit, and in the sides are numerous small openings, having 

 a maximum width of about i mm., which \re probably the en- 

 trances of inhalent canals. The sponge is soft and yielding to the 

 touch and probably the roughness of the surface is exaggerated by 

 shrinkage. The spicules agree in size and shape with those of the 

 specimen from Unalaska Island, referred to by the writer in vol- 

 ume xii of the Royal Society's Transactions. 



Craniella cranium is also well known from North Atlantic waters 

 generally and Fristedt in his "Sponges from the Atlantic and Arctic 

 Oceans and the Behring Sea " mentions three specimens obtained 

 off the east and west coasts of Greenland. Mr. Low's specimen 

 is somewhat ovate in shape, broadly roundeJ above and prolonged 

 downward below where the basal strands have the appearance of 

 having been attached to some foreign object; total height locent., 

 maximum breadth 4.5 cent., surface uneven, monticulose. The 

 extreme summit is abraded. The measurements of the spicules 

 agree with those given by Sollas in his description of the species 

 (vide Report Tetractinellida, Challenger Expedition vol. xxv). A 

 point of some interest is that the spicules of Craniella Logani, 

 Dawson, from the Leda clay at Ottawa and Montreal, are 

 practically identical in shape and size with those of Mr. Low's 



