36 



ECHINOIDEA. II. 



the pvramid (5) of the odd posterior interambnlacrnni being considerably larger than the others. (Comp. 

 Loven. Echinologica. p. 69). 



The spincs are a little longer than in pusilhis, the largest being ca. i"™, and more .slender. 

 Thev are provided with only a few serrations and end in rather a .slender point. (PI. XII. Fig. 15.) The 

 miliary spines are onl}- abont one third as long as the primar\- ones. They are a little sienderer than 

 those of pusillus, often slightly serrate near the npper end. The endcrown is a little larger than in 

 piisilliis; the longitndinal ribs are more widened at their npper end, almost joining with their edges, 

 and the radial piates are larger and broader, generally with 4 — -5 serrations, sometinies in a donble 

 series. (PI. XII. Figs. 10, 16). — The pedicellariæ also differ rather considerably from those of piisillus. 

 The ophicephalous pedicellariæ differ from those of ptisillus in having fewer serrations along the edge 

 of the blade, otherwise the sliape and structnre is the same as in that species. (PL XII. Figs. 8, 11 — 13). 

 The tridentate pedicellariæ (PI. XII. Figs. 25, 28) are gradually narrowed towards the articular snrface, 

 whereas in pitsilhis they narrow abrnptly at the lower end of the blade. The triphyllous pedicellariæ 

 I PI. XII, Fig. 21) have a much broader blade than in pusillus, and the edge is much more closely ser- 

 rate; they are very small, the head only ca. 0-04™". — The bnccal tube-feet are not distinctly larger 

 than the other actinal tnbe-feet. Spicnles are wanting as in pusillus. 



To this species so well distingiiished by its large ocnlar pores, little developed petals, few 

 actinal pores, as well as by its spines and pedicellariæ, belong all the specimens of <Ecliinocyamus 

 pusillus« from the -i^Blake* and Albatross which I have seen (viz. from vBlake> St. 5 and 239, 

 'Albatross vSt. 2352, 2666 and 2668), as well as the specimens from the Challenger:- St. 122 (e.xamined 

 in the British Mnsenni); a pair of specimens dredged b>- myself in 500 fathoms off Frederiksted, St. 

 Crnz, also belong to this species. Probabh' all the specimens of Ecliinocyanius recorded from the West 

 Indies and Florida (and Brazil) nnder the name of pusillus > will tnrn ont to belong to this species 

 (and perhaps parth- to the following species). In any case the existence of Ech. pnsilbis in these 

 regions mnst remain donbtful, until bv renewed carefnl examination it is proved beyond doubt to 

 exist there besides Echinocyavius gnvidiporus. I have fnrther seen rather numerous specimens of this 

 species from the Azores from depths of ca. 100 — 700 fathoms (1365 m.) and from the Josephine Bank 

 (1 10 — 430 fathoms). 



The occnrrence of this species on both sides of the Atlantic is in good harmony with the dis- 

 tribntion of other Echinoids, e. g. Goiocidaris iiiaculata. Cidaris affiuis a. o. — and likewise it wonld 

 not be contrar\- to these facts of geographical distribntion, if Ech. pusillus should tnrn out to occur 

 in the West Indian Seas; it mnst onl\- be emphasized that it cannot be considered as an established 

 faet, before the specimens of grandiporus (and possibly also of inacrostoiuus) are distinguished from the 

 trne pusillus by renewed examination. 



Echinocyamus macrostomus n. sp. The .shape of the test (PI. XII. F^igs. 17, 24) is very like 

 that of grandiporus. a little more elongated, but not so much that it can be relied upon as a specific 

 character. The peristome is generally very large; there is, however, some variation in this resjDect, 

 but I have ahvays found it considerably larger than in specimens of graudiporus of a corresponding 

 size. The edge of the peristome is not incurved; the buccal membrane is devoid of spicnles as in the 

 other species. The anal opening is generally larger and nearer the edge of the test than in graudi- 



