ERYLUS SOLLASII. 273 



three groups, which I consitler as three distinct races. These I denominate I, 

 II, and III. Race I contains four forms; the races II and III one each. The 

 four forms of race I are designated A, B, C, and D. To race I, form A, belongs 

 the partly light and partly dark specimen from South Molokai (Station 3847) ; 

 to race I, form B, the small, entirely dark specimen from South Molokai (Sta- 

 tion 3847); to race I, form C, the two large whitish specimens from South 

 Molokai (Station 3848); to race I, form D, the middle-sized, hght-coloured 

 specimen from northeast Hawaii (Station 4062) ; to race II the large dark 

 specimen from South Molokai (Station 3849) ; and to race III the large dark 

 specimen from northeast Hawaii (Station 4055). 



Shape and size. The smallest specimen is the entirely dark one from 

 Station 3847 (race I, form B). It is massive, lobose, covered with small but 

 relatively high gyriform ridges, and measures 18 by 9 mm. It has one oscule, 

 about 1 mm. wide, which lies on the summit of a slight elevation. The partly 

 light, partly dark sjjccimen also from Station 3847 (race I, form A) is an irregu- 

 lar mass, with still higher gjTiform ridges and measures 24 by 17 by 13 mm. 

 It has two oscules, the larger 1.8 mm. in diameter, and numerous small pores, 

 which are scattered over its surface. The specimen from Station 4062 (race I, 

 form D) is meandric, has small, but relatively quite high, gjTiform ridges and 

 measures 36 by 27 by 18 mm. Here and there small apertures are observed on 

 its surface. Of the two specimens from Station 3848 (race I, form C) one (Plate 

 1, fig. 27) is meandric, while the other appears as a mass with lobose, somewhat 

 digitate processes 7-12 mm. thick. The former measures 60 by 35 by 20 mm., 

 the latter is only 51 mm. long. A few oscules, up to 1.5 mm. wide, are situated 

 on the elevations, and groups -of small pores are scattered over the other parts 

 of the surface. The specimen from Station 3849 (race II) (Plate l, fig. 28) 

 appears as an aggregate of vertical digitate parts about 15 mm. thick, which 

 are joined for the greater part of their length. It is 73 mm. high, 64 mm. long, 

 and 42 mm. broad. From the surface ridges protrude which are about 1 mm. 

 high and 2.5 mm. apart. These ridges are somewhat curved and most of them 

 extend longitudinally, parallel to the vertical axis of the sponge. On or near the 

 summit of each digitate protuberance an oscule is situated. The largest of these 

 oscules is oval and measures 3.2 by 2 nim. ; the other oscules are 1-2.5 mm. wide 

 and more or less circular. On the sides of the digitate parts groups of small 

 pores are met with. At one place there is a group of six much larger apertures 

 about 1 mm. wide; here the sponge seems to have been injured some time before 

 its capture. The specimen from Station 4055 (race III) (Plate 3, fig. 27) is an 



