ECHINOIDEA. II. lie 



Sc/i. fragilix. and even more the qnite similar devclo])ment of the fascioles in . I Iki/ lis ca7<cri/osns, where 

 botli lateral and anal fascicle generally disappear with age, shows that the latero-anal fascicle is part 

 of the primary fascicle. 



Sell, fragilis was taken ])y the «Ingclf»-Expedition at tlie following stations: 



St. 25 (63° 20' Lat. N. 54" 25' Long. W. 5S2 fathoms 3°3 C. Bottom temp 



- 27 (64° 54' - 55° 10' - 393 - 3°8 - 



- 28 (65° 14' - 55° 42' - 420 - 3°5 - 

 _ 32 (66° 35' - 56° 38' - 318 - 3°9 - 



- 35 (65° 16' - 55° 05' - 362 - 3"6 - 



— 54 (63° 08' — 15° 40' — 691 — 3°9 — 



— 81 (61° 44' — 27° 00' — 485 — 6°i — 



— 85 (63° 21' — 25° 21' — 170 — — 



— 89 (64° 45' — 27° 20' — 310 — 8°4 — 



- 97 (65° 28' - 27° 39' - 450 - 5°5 - 



The species was further taken in the Davis Strait by Wand el 1889 (63° 56' l^at. N. 53° 12' 

 Long. W. 130 fathoms, i specimen). Several specimens were taken at the Faroe Islands (150 — 190 

 fathoms) by the author in 1899 and by Ad. S. Jensen f«Michael Sars>. 1902). 



Tlie bathymetrical distribution of this species is ca. 35—700 fathoms. In the Challenger»- 

 Echinoidea, p. 221 it is stated to have been taken (by the «Blake») at a depth of 955 fathoms at the 

 ^-Caribbean Islands \ I cannot find in the Preliminary Report on the «Blake>-Echini (Bull. Mus. Comp. 

 Zool. VIII. 1880. Nr. 2. p. 84) or in Professor Rathbun's works any locality to which this statement 

 might refer. — The geographical distribution of Scli. fragilis is : from the Northern Norway to the 

 Faroe Channel, South of Iceland, Davis Strait and along the American coast down to Florida. On the 

 European side of the Atlantic it is not known farther south than the Faroe Channel, and it is not 

 known from the Mediterranean or the Azores. 



Sars (loc. cit.) and recently Grieg (loc. cit.) point out that Scli. fragilis is both more connnon 

 and reaches a considerably larger size at Northern Norway than farther South; thus it reaches a 

 size of 90'"'" length at the Northern Coasts, whereas the largest specimens known from Bergen are 

 only 55""". (A specimen from the Faroe Lslands has the same size, and a specimen from the American 

 Coast (S. of Long Island, 302 fathoms) is 60™'" in length). ■: It is therefore without doubt to be regarded 

 as an arctic form'. It is certainly a remarkable fact that the largest .specimens are from the most 

 northern locality, but nevertheless Scli. fragilis is evidentl}- no arctic form. It is not found in the cold 

 area of the Norwegian Sea, occurring only where the bottom temperature is positive. It is one of 

 those rather numerous species, which belong to the Northern Atlantic, the warm area, but, on account 

 of the peculiar hydrography of the Norwegian Sea, proceed far North along the Norwegian Coast. 



In the V Challenger :>-Echinoidea (p. 201 — 2) Scli. fragilis is recorded from the Cape of Good 

 Hope, and recently Professor Bell' likewise records the .species from vSouth of Africa. Doderlein 

 (Op. cit. p. 250) supposes that tliese specimens are really Scli. cafoisis Studer, of which species a careful 

 description and figures are given. Having myself examined the type specimen of the Sch. capaisis in 



' The Echiiioderina found off the Coast of South Africa. I. Echinoidea. Marine Investigations in South .Africa. III. 

 1904. p. 175. 



15* 



