ECHIXOIDEA. I. 161 



ParecAtnus, although it is not equally marked in all of them. On the buccal plates and on a few of 

 the other plates in the buccal membrane some small, club-shaped spines of a length of a couple of mm. 

 are found (PI. XX. Fig. 24). As these spines are found in no other genuine .&7//y/^.f-species '), they are 

 an excellent distinguishing character of this species; they are, however, not found in quite small indi- 

 viduals, until these have reached a diameter of ca. i5 mm . 



The buccal membrane contains numerous, more or less complicate fenestrated plates (PI. XVI. 

 Fig. 12); in larger specimens some of these are so large and thick, that they are seen as small knobs 

 on the dried buccal membrane. Inside of the buccal plates they are more numerous and smaller, and 

 are arranged in radiate series. A few bihamate spicules are rarely seen in the buccal membrane. 

 In the gills they are found in larger numbers together with the common irregular fenestrated plates. 



The pedicellarise. The globiferous pedicellarise (PI. XIX. Fig. 24) with 1 — 1, sometimes 1—2 

 lateral teeth, otherwise without marked peculiarities. The trideutate pedicellarise (PI. XVIII. Figs. 13, 20) 

 have a long, narrow, rather deep blade ; from the upper end of the apophysis some mesh-work reaches 

 a longer or shorter way into the blade; in small pedicellarise no such mesh-work is found (Fig. 13). 

 Oulv at the point, where the valves join, the edge is somewhat serrate; in the other part it is straight, 

 but set with small teeth placed in transverse series as in the other Ec/i/'n/is-species. The ophicephalous 

 and triphyllous pedicellarias of the common form; sometimes, however, may be found a few large, 

 elongate ophicephalous pedicellarise, quite as those described above in Ech. AlexandrL The sphseridise 

 (PI. XIX. Figs. 28, 30I with few grooves, sometimes a little thorny. Spicules (PI. XVIII. Fig. 12) of the 

 common' form. 



By the Ingolf -Expedition this species has been taken on the following stations: 



St. 6 (63 c 43' N. L. 14" 34' W. L. 90 fms. Bottom temp. 7 5). 2 specimens. 



-54(63° 08' - 15° 40' - 691- 4 2). 2 



— 86 (65° 04' — 23° 48' — 76 - ? ). 1 



— 89 (64° 45' — 27° 20' — 310- 8°o). 1 



Otherwise it is found along the European coasts from Britany to Spitzbergeu and Iceland. 

 Hoyle (op. cit.) mentions it also from the coasts of Spain and Portugal and from the Mediterranean, 

 and Bell (Catalogue) further notes it from Port Natal and Brazil. The two last statements I must suppose 

 to be incorrect, whether they are owing to wrong determinations or wrong labelling. A so wide 

 distribution of a littoral species would be something quite exceptional, and if this large, conspicuous 

 species were really found on the coasts of South Africa and Brazil, we should certainly have sufficient 

 statements of this fact. I must also regard its occurrence in the Mediterranean as doubtful, probably 

 owing to a confounding with other species [acutusl). When Hoyle cites Cams as an authority for 

 its being found in the Mediterranean , it must be owing to a misapprehension. Cams, in his Pro- 

 dromus Faunse mediterranean, does not mention this species, but only Ech. esculentus Lamk. (notL.) 

 as a synonym of Sfhmrech. gran it Inn's. Sluiter (371) also mentions a specimen of Ech. esculentus L. 

 from the Mediterranean, but I cannot regard this museum-statement as quite reliable either. 



i) In the description of Ech. lucidus by Doderlein (114) it is said: Das Buccalfeld ist glatt bis auf 10 massig grosse 

 Plattchen, deren jedes einen grosseren Tuberkel und einige Pedicellarien tragt . This might indicate that also in this species 

 spines may be found on the buccal plates. On the specimen I have examined, I have not, however, seen any such spines. 



The Ingolf-Expedition. IV. I. 21 



