76 ECHINOIDEA. II. 



ends down on the sides, not reachin«^ tlie edge. There is a soniewhat larger, thougli very iuconspicuous 

 tootli at the point. In larger specimens (PI. XI. Fig. 24) the valves beconie more slender and elongated 

 and the tooth at the point more prominent, and in the largest ones (ca. o-2""" head) the tooth at the 

 point is very long, tiie blade narrow, the edges serrate onh' in the outer part, where the wilves join. 

 (PI. XI. Fig. 5.) — The rostrate pedicellariæ (PI. XI. Figs. 17, 27, 28) differ considerably from those of 

 P.Jeffrcysi and Waiuh:li. The blade has not the outer edge sharply set off from the sides; the point 

 is simj^ly rounded, set with some slender teetli, which continne some way down the side-edges; the 

 edges are rather thick, having only a small deepening along the middle of the blade with few holes 

 there, and sometimes near the point a transverse beam, which mav be provided with a tooth. These 

 pedicellariæ mav be invested in a rather thick, pigmented skin. — The ophicephalous pedicellariæ 

 (PI. XI. Figs. 3, 6, 32) are not so beautifully developed as in Jcff'rrysi and Wmidcli. though agreeing 

 in the main points with these. The outer end of the valves is hardly widened and with rather few 

 teetli along the edge. I have found only two specimens of them, at the anal area. Also the rostrate 

 pedicellariæ occnr mainly near the anal area; the larger tridentate pedicellariæ I have found within 

 the oral invagination. 



Regarding the iuner anatomy I caunot gi\'e fuU infornuition, as I do not want to destroy 

 one of the better preserved specimens. In a crushed specimen the intestine is preserved; the walls 

 are, however, so incrusted with the Cilobigerina-mud, which fills the intestine, that it is impossible to 

 discern the convohitions with certainty; likewise I am unable to ascertain the presence of a diverti- 

 culum or of the siphones, though it eau scarcely be doubtful that they will be present as in other 

 Pourtalesiæ. — As in P. Jeffrcysi and Wandcli the genital organs differ considerably in shape in the 

 two sexes: large, bush-shaped in the males, simple tubes in the female. The male genital organs are 

 situated one behind the other, far back, the posterior one at the beginning of the body; , and connect 

 with the genital openings through ver}' long efferent duets, passing up the whole length of the neck. 

 (PL VII. Fig. 16.) In the female the genital organs are situated in the head , having rather shortoviduct.s. 

 (PL VII. Fig. 10). The stone-canal evidently runs as in P. Jeffrcysi, making a great curve backwards, 

 following the intestine iuto the body; to be sure I have been unable to trace it in its whole length, 

 onh- the two ends of it (PL VII. Fig. 16), but the faet that it passes backwards through the whole 

 length of the neck along the dorsal side does not leave any doubt that its course must upon the 

 whole be as in /-". Jeffrcysi. There is a slight thickening, representing the axial organ, near the upper 

 end of the canal. Below the ankylosed genital-madreporic plate there is a rather large calcareous pro- 

 cess, to which the end of the stone-canal is fastened. The radial water-canals of the bivium are very 

 thin and iuconspicuous, those of the trivium are more distinct; ampuUæ I have been unable to find. 



This species was taken by the Ingolf at the following stations: 



St. 40 [bi' 00' Lat. N. 21" 36' Long. W. 895 fathoms t^°t^ C. Bottom temp.) 1 specimen. 



— 68 (62" 06' — 22° 30' — 843 — 3°4 — — I (2?) — (fragments) 



— 83 (62'' 25' — 28° 30' — 912 — 3°5 — — 4 — (two in fragments). 



The species is thus known only from off Southwest Iceland, from a depth of 843 — 912 fathoms. 

 That it will prove to be distributed o\er a large part of the warm area of the northern Atlantic can 

 scarcely be doubted. 



