42 



JAMES A. GRIEG 



[REP. OF THE "MICHAEL SAR3 J NORTH 



in microstoma than in norvegicus. Mortensen 1 ), however, 

 very justly remarks that this distinction is not reliable 

 either, as the size of the buccal area is subject to consi- 

 derable variations in norvegicus. 



Echinus acutus is an east Atlantic species, ranging 

 north to the Beeren Eiland ("Voeringen", stat. 275, 74° 8' N.) 

 and south to the Mediterranean and Cape Bojador ("Val- 

 divia", stat. 28, 26°17'N.) The bathymetrical distribution 

 is — 1280 m. It is a true warm-water species, but the 

 variety norvegicus is taken in the cold area by the "Voe- 

 ringen" (stat. 267, 71°42'N. 37°1'E, 271m., -j- 1.4°, 

 and stat. 275, 74 ; 8' N. 31° 12' E., 269 m, ~ 0.4°). 



Echinus alexandri Danielssen & Koren. 



Echinus alexandri Danielssen & Koren, Nyt Mag. for Naturvidensk., 



vol. 27, 1883, p. 294, tab. 3 & 4. 



1S ,7, stat. 88, 45° 26' N. 25° 45' W., 3120 m., sand and yellow mud, 

 temp. 2.5° Cel. Very Common. 



- : :, stat. 95. 50' 25' X. 1 1' 44' W., 1797 m., temp. 3.5° Cel. 18 

 specimens. 



The test-diameter of the smallest specimen was 25 mm., of the 

 largest 46 mm. 



Echinus alexandri is indigenous to the great depths 

 of the North Atlantic, where it has been found on the 

 west as well as the east side. It ranges south to the Azores 

 ("Princesse Alice", stat. 743, 37° 35' 45" N. 26° 26' 15" W., 

 1494 m.) There is no proof yet of its occurrence on the 

 banks that separate the Atlantic from the Norwegian Sea, 

 but it must no doubt occur there, as it has been taken 

 by the "Voeringen" on their slope toward the Norwegian 

 Sea (stat. 76, 69° 18' N. 14 D 33' E., 980 m., -=-0.2"). The 

 bathymetrical distribution is 790—3120 m. 



Echinocyamus pusillus O. F. Miiller. 

 Spatangus pusillus O. F. Miiller, Zol. Dan. Prodr., 1776, p. 236. 



20 /o, stat. 38, 26 r 3'X. 14°36'W., 77 m., red sand and shingle. 

 Several specimens. 



Echinocyamus pusillus is an east Atlantic species 

 ranging north to the Porsangerfjord and south to the 

 Mediterranean, Cape Bojador and the Azores. Its bathy- 

 metrical distribution is 0—800 m. (Mortensen). According 

 to Koehler it has, however, been taken at a depth of 

 1250 m. 



Hemiaster expergitus Loven. 



Tab. 5, figs. 11 & 12. 



Hemiaster expergitus Loven, Kgl. Sv. Vet. Akad. Handl., vol. 11, 



no. 7, 1874, p. 13, tab. 5, figs. 46 & 46, tab. 11, figs. 93 & 94, tab. 13. 



figs. 114— 120, tab. 26. 



18 /?, stat. 88, 45° 26' N. 25° 45' W., 3120 m., sand and yellow mud, 

 temp. 2 5" Cel. One specimen which measured: 



') Mortensen: Echinoidea, part 1, 1903, p. 149. 



Length 53.5 mm. 



Breadth 52.5 „ 



Height 30.5 „ 



Breadth of mouth 6 „ 



Breadth of anal area 5 



Breadth in per cent of length . . 98.15 „ 



Height in per cent of length . . . 57.01 „ 



The type specimen was 14 mm. long and the speci- 

 mens described by Mortensen measured as much as 37 

 mm., J ) which has represented up to the present time the 

 maximum size of this species. But as the foregoing 

 measurements show Hemiaster expergitus may attain 

 considerably larger size. The form of the spines and of 

 the pedicellarias agrees perfectly with the description given 

 by Mortensen. I have therefore in spite of its large size 

 referred the specimen to Hemiaster expergitus. 



Hemiaster expergitus is a North Atlantic species, 

 ranging from the Caribbean Sea to the Davis Straits on 

 the west side and from Iceland to the Cape Verde Is. 

 on the east side. The "Michael Sars" found it in 1902 

 on the banks north-east of the Faroe Is., "Tampen" 

 (stat. 51, 61° 40' N., 3° 11' E., 400 m„ 6.34°) but with 

 this exception it is only known from the great depths of 

 the North Atlantic. The bathymetrical distribution is 

 400 — 3120 m., but its main distribution seems to be at 

 depths greater than 1000 m. 



Spatangus raschi Loven, 

 Spatangus raschi Loven, 0fvs. Kgl. Vet. Akad. Ferhandl. vol. 26, 

 1869, p. 733, tab. 13. 

 "A. Stat. 4, 49° 38' N., 11° 35' W., 923 m, sand and mud, 

 temp. 9.2° Cel Common. 7 specimens were preserved. 



"/-. Stat. 96, 50° 57' X., 10° 46' W., 184 m., temp. 11° Cel. 

 8 specimens, of which one was preserved. 



As may be seen from the following table, the form 

 of the test is subject to considerable variations, particularly 

 in regards its height. While thus in the specimens from 

 stat. 4 the breadth of the test varies between 89. s and 

 94.05 per cent of the length, the height varies between 

 47.92 and 62.5 per cent of the length. 



Length 81 84 86.5 (stat. 96) 87 93 96 98 100 



Breath 74 79 78.5 78.5 86 87.5 88 94 



Height 45 52 45 49 57 46 55 58 



Breadth of mouth.... 11 11 11.5 15 16 11 11 14 



Breadth of anal area 8 8.5 8.5 8 8 9.5 9 10 



Breadth in % of length 91.36 94.05 90.75 90.23 92.58 91.15 89.8 94 



Height in % of length 55.56 62.5 52.02 56.32 61.29 47.92 56.12 58 

 All measurements are in millimetres. 



Spatangus raschi is an east Atlantic species, ranging 

 south to the Azores and north to the banks off Tromsoe 

 ("Voeringen", stat. 173 B, 69° 18' N., 14° 32' E., 549 m.) 

 It is a decided warm water species, which was only once 



'). Mortensen: Echinoidea, part 2, 1907, p. 97. 



