SPONGES FEOM THE WESTERN COAST OF NORTH AMERICA. 127 



Suberites domuncuki, Schmidt. 1S62. Spong. Adriat. Meeres, p. 67. 



Hymeniacidon subcrea, Boweibank. 1864. Mon. Brit. Sponj|., vol. i., p. 191; vol. ii., p. 200; vol. iii., pi. xxxvi-, 

 figs. 1, 2, 3, 4 : vol. iv., p. 88. 



There are nearly sixty specimens of this species from Alaska. Carter, in the Ann. and 

 Mag. Nat. Hist., series 5, vol. ix., p. 3.53, has noticed the occurrence of a " flesh-spieule " 

 in this species, which he describes as being " a short, curved, cj'lindrical acerate with 

 obtuse ends, inflated in the centre and microspined." 



In the Alaskan s^jecimens the flesh-spicules are present in the majority of cases, but 

 absent in a few ; in some specimens they occur in great abundance, in others only one or 

 two were seen. Evidently the presence or absence of the flesh-spicules cannot be con- 

 sidered of specific value. In the 'Transactions of the Royal Society of Canada,' 1892, the 

 writer described a sponge, of which there were five specimens, from Vancouver Island, 

 under the name S. latiis, believing them to be distinct from S. suberea on account of the 

 non-existence of flesh-spicules in the Vancouver specimens. Since then one or two of 

 these spicules have been seen in some of these specimens, in which case the Vancouver 

 specimens must be regarded as identical with S. suberea, .Johnston. 



In some of the sponges the tylostyli were rounded ofl' and quite blunt at the end that 

 is normally rather sharply pointed (Plate IV., fig. 3). The flesh-spicules were also seen in 

 all stages of transition, from being almost spherical in shape to the pei-fect spicule (Plate 

 IV., fig. .3d). 



The tylostyli have a maximum size of about 0-406 by 0-009 mm. (Plate IV., figs. 3a, 

 3b) ; the small cortical tylostyli have an average size of 0-091 by 0-006 mm. (Plate IV., 

 fig. 3c). 



The " inflato-cylindrical flesh-spicules" attain a length of 0-032 mm. and vary in 

 thickness from 0-003 to 0-0049 mm. 



Distribution. — Behring Sea and North Pacific Ocean. 



SuBEKiTEs MONTALBiDUS, Carter. 

 (Plate III., figs. 6, 6a— c.) 



Suberites montnlbirtm, Carter. 1880. Ann. and Mag. Nat. Hist., series 5, vol. vi., p. 256 ; vol. ix., p. 353. 



Suberites spec, Vosmaer. 1882. Report on tlie sponges dredged up in tlie Arctic Sea by tlie " Willem Barents " ia 



the years 1878 and 1879 (reprinted from the " Nied. Arch, fiir Zool.," Suppl. Band i.), p. 32, pi. i., 



figs. 22, 23; pi. iv., figs. 140-144. 

 Suberites monlalbidm, Fristedt. 1887. Sponges from the Atlantic and Arctic Oceans and the Behring Sea (trans- 

 lation), Vega-expeditionens vetenskapliga arbeten, p. 428. 



This sponge was first described by Carter from a specimen from Barent's Sea, near the 

 southwest end of ISTovaya Zemlya. Vosmaer's specimens were from the same region, and 

 later Fristedt records the occurrence of the same sponge in Behring Sea and Strait, in 

 Beaufort's Sea, the Siberian Arctic Ocean, the Kara Sea, the European Arctic Sea and 

 Barent's Sea and the sea west from Greenland. 



A single specimen, west from Unalaska Island, represents the species in the present 

 instance ; it is amorphous, about 25 mm. long, 13 mm. broad, and quite soft and spongy to 

 the touch. 



The spicules of the Alaskan specimen are : — (1) Large tylostyli with scarcely any 

 increase in thickness at the basal end (Plate III., fig. 6) ; varying in length from 0-334 to 



