KCHINOIDKA. II. • g. 



species from ^l. fnlva. tlial no < spatelfonnige ■ spines occur inside tlie fasciole (evidenllv jndging- from 

 A gas si z' statement in liis description of tlie large form tiiat within the peripetalous fasciole the 

 spines are longer, not clnl)shaped ); this does not hold good, at least in the specimens before me. 

 De IMeijere further finds a difference in the structure of the spines of the two .species, viz. that in 

 A. fnha the widened point of the spines is serrate along the edge, whereas it is smooth in .[.rostrata 

 — founding on the figure (PI. XLL 7 evidently) given by Agassiz. This character will not hold good 

 either; the widened part of the spine is (more or less) serrate at the edge also in ^i. rostrata. — The 

 small spines and clavula; have an ampulla" at the point, as found by de Meijere in A. fiilva 

 (PL XV. PMg. 43). — The sphaeridia; are .slender, generally rather elongate; in the anterior ambulacra 

 they continue up to the fasciole, in the posterior to the anal area. 



Pedicellarise. Only rostrate and tridentate pedicellariae have been found. The rostrate pcdi- 

 cellaria; (PI. XV. Figs, i, 13) have almost straight, flat valves, with the point rounded, not widened, 

 faintly serrate; neck very short; the stalk may have a faint milled ring below. The head is ca. o-=5""" 

 in length; the strong brownish adductor muscles between the valves make these pedicellari<e rather 

 conspicuous. The\- may occur very numerously over the whole test, or very sjDaringly. The tridentate 

 pedicellaria; (head up to i"^'" in length) have simple, leafshaped valves, which join in almost their whole 

 length. In large specimens the edges are bent somewhat inwardly in the lower part of the blade and 

 very irregularly serrate. The blade may be open down to the apoplusis, or the edges mav unite to 

 form a coverplate over the lower part; generally there is no meshwork in the blade, but in a s])eci- 

 men examined in the Museum of Yale College I found the larger tridentate pedicellaria; with a rather 

 richly developed meshwork (PI. XV. Fig. 2). The basal part is rather narrow; the edges may be some- 

 what serrate. The neck is short, the stalk without a anilled>> ring below. They occur in all sizes from 

 quite small to ca. i""" length of head. (1^1. XV. Fig.s. 8, 21, 29, 52.) Quite small forms (PL XV. P'ig. 37) 

 may perhaps better be termed triphyllous. According to a sketch of a living specimen made on board 

 the Ingolf the colour is light yellow, the fasciole alone being of a prominent brown colour. In some 

 specimens seen in the Museum of Yale College the frontal tube-feet were violet. — 



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



St. 36 (61° 50' L,at. N. 56° 21' Long. W. 1435 fathoms. i°5 C. Bottom temp.) 3 specimens. 

 -37 (60° 17' - 54^05' - 1715 - i°4 - - )5 - 



The geographical distribution, as far as hitherto known, is the Northern Atlantic, at the Ame- 

 rican side, and the Davis vStrait; the batlninetrical distribution is 1240 — 1750 fathoms. In the Chal- 

 lengers-Report the species is stated to occur also in the I>a)- of Biscay and at the Coast of Portugal, 

 as also in the Arafura Sea (Chall. St. 191. 800 fathoms). That the specimen from the latter localit>- is 

 wrongly referred to A. rostra fa I have shown above. Regarding the locality Bay of Biscay and Coast 

 of Portugal^' it may be remarked that in Sunmiary of Results of the . Challenger -E.xpedition I. 

 p. 114 A. rostrata is named from vSt. 2, off the Mouth of the Tagus, 470 fathoms; but since the 

 specimens were without distinctive. Station number, it seems not to be relied upon that the 



I I name it thus, as it is evidentl}- a structure of the same kind as the ampullar in the secondary spines of some 

 Cidarids, described hy Ham an n and Prouho. 



- Duncan (Revision, p. 270) from this expression conchules that one specmien was taken in the Kay of Biscay, 

 later on another off the coast of Portugal, which there is nothing else to support. 



