jjQ ECHINOIDEA. I. 



peculiarities; triphyllous pedicellariæ I have not seen. In the globiferous pedicellariæ nnmerous 

 spicules are fonnd, somewhat thickened in the ends (PI. XXI. Fig. 24. a), although not markedly dumb- 

 bell-shaped; also a few common bihamate spicnles are fonnd among them. In the tube feet the biha- 

 mate spicules are predorainant, but the other form is also fonnd. — De Loriol, no doubt, is right 

 that this is a distinct species; but it is no Echiniis. Its nearest relations are iEchinusi verruculatus 

 and especially darnleyensis. 



Echiinis darnleyensis Woods. Of this species I have had occasion to examine a specimen from 

 Thur.sday Island, Torres Strait, 4 fathoms (the : Alert >-Expedition) in British Museum. (I cannot 

 answer for the correctness of the determination; that it corresponds with the description is no guar- 

 antee for its being the same species, as the description gives only the usual things: spines, tubercles 

 etc, but mentious neither spicules nor pedicellariæ.) A primary tubercle is fonnd on every ambulacral 

 plate; according to Woods (442. p. 165) the ocular piates are quite shut off from the periproct — but 

 according to an information from Prof. Bell they are not shut off from the periproct in these speci- 

 mens (I have forgotten to ascertain it myself). The buccal membrane is quite naked with the excep- 

 tion of the buccal piates which are placed in pairs opposite to each other, and carry a few pedicellariæ. 

 «With ten rounded small openings surrounded by Pedicellariæ«, it is said in the description by Woods; 

 this, I think, must be the holes in the buccal piates for the buccal tube feet — a rather common 

 feature to note in a description of species! Innermost in the edge of the mouth numerous needle- 

 shaped, more or less irregular spicules are fonnd resembling those of <.'.Ec/i.i> Robillardi\ they are 

 arranged parallel to the edge of the mouth; a few are a little fenestrated. Outside of these some 

 bihamate spicules are fonnd, but far from so great a number as in Robillardi. Near the gills numerous 

 bihamate spicules are found in the buccal membrane. The gills themselves contain the common irre- 

 gular fenestrated piates. According to Woods the auriculæ are only ^slight thin processes, which do 

 not meet ; Prof. Bell informs me that they are here of the common form. (In verriicnlatus and Robil- 

 lardi they are also of the common form.) The globiferous pedicellariæ as in Sphærechimis , only is 

 the blade uncommonly short (PI. XXI. Fig. 36). In the tridentate pedicellariæ (PI. XXI. Fig. 7) the blade 

 is broad, open, with only a slight net of meshes in the bottom. The edge is finely, simply serrate in 

 the outer part where the valves join; in the lower part a few larger indentations are found. The 

 valves are rather wide apart. Ophicephalous and triphyllous pedicellariæ of the common form. The 

 spicules (PI. XXI. Fig. 23) of the globiferous pedicellariæ arcuate, but not pointed at the ends; in the 

 tube feet only a few bihamate spicules are found. — Woods thinks that it is this species Agassiz 

 has wrongly referred to Ec/i. magellaniciis\ that it has nothing to do with magellaninis is certain, 

 although the differences pointed out by Woods: dn the actinostome being larger; in the abactinal 

 system, where the genital piates have onl}- two tubercles, and in the color of spines and test are 

 quite irrelevant. The principal difference is to be found in the globiferous pedicellariæ and the spi- 

 cules; they show that this species is no EcJiimis or Sfcrcchiiius at all, but like Ecli. Robillardi and 

 verruculalns is closely allied to Toxopneiistcs and Tripnetistes. 



To the genus Toxopnenstcs Ag. are referred the species: -niaculatits (Lamk.), pileohis (Lamk.), 

 clegans Doderl, varicgatus (Lamk.), and semitnbcrculatus (Val.); to the genus Tripncustes Ag. (in Re\'. 

 of Ech. this genus is called Hipponoé) are referred the species: esculentus (Leske), depressus Ag., and 



