ECHINOIDEA. I. 121 



trofus. In onr ninseuni is fouiid a small Ecliinid from Japan, received from the museum in \"ienna 

 under the name of Str.iiifrniirdiiis: tliis determination is scarcely correct, but it might agree with the 

 description of cJiloroccntrotiis. At all events it is another species than that of de Loriol; it has four 

 pairs of pores, wliile Brandt gives 5 pairs. (That of de Loriol has 7 — 5 pairs). In this specimen the 

 globiferous pedicellariæ are as in drobacliiciisis; but the spicules are simple, bihamate. Nothing definite 

 can be said of Str. chlorocenfrotus, nntil the type specimen has been reexamined. 



To the species here mentioned, especially intcrmedhis and chlorocentrotus (?) has to be added 

 <i.Sphærechmusr, pjilclicrruiius^ of which I have received a couple of specimens from Prof. Doderlein; 

 some specimens of this species were further found among some Echinids from Japan, which Prof. 

 d'Arcv Thompson has sent me for examination. Of this species I shall give the following informa- 

 tions. A primary tubercle is found on all the ambulacral piates (as in all the preceding species and, 

 as far as I know, in all polypore species). Only four pairs of pores in each are, as in iutrriiicdiiis and 

 cliloroccntrohts (mentioned b\- Agassiz). Three ocular piates reach to the periproct. The buccal mem- 

 brane is highlv pigmented, with numerous small fenestrated piates, some few of those outside the buccal 

 piates thick, with pedicellariæ. The globiferous pedicellariæ quite as in drobacliieusis; of tridentate 

 pedicellariæ a larger form is found (PI. XX. Fig. 10), a little widened at the point and with rather 

 sinuate edge, and a smaller form, where the edge is straight or only very slightly sinuate. The other 

 pedicellariæ show no peculiarities. The spicules are bihamate, not branched. 



As none of the other species referred to Strongylocciitrotus — and, upon the whole, no other 

 Echinids of c Triplrc/iii/idæ and Ecliiiio^nctradæ that I know, with the exception of ihe Aiif/incidaris 

 hoDialostovia Ltk. mentioned below — have the same peculiar form of globiferous pedicellariæ, it is 

 evident that the mentioned species form a separate group, while it is a less sure faet whether they 

 forur also oue genus. The species pulclicrrinius, intcrmcdius., and chlorocciitrotiis (?) are distinguished 

 from the others by haviug simple bihamate spicules, onl\- four pairs of pores in each are, and by the 

 very flat form of the test; in all of them the spines are very short, the priniar\- ones very little con- 

 spicuous, also the primary tubercles are onh' little conspicuous among the numerous secondary 

 tubercles arranged in horizontal series. I am most inclined to interpret these species as a particular 

 genus (thev form, perhaps, even only one species), which genus, if the mentioned specimen should 

 really prove to be ideutical with Braudt's .9/;'. cJiloroccntrotiis, must get the name of Stroiigylocrntrotns. 

 The other species: drøl)achiensis, purpiiratus^ a.\\å fraiuiscaiiits, would then have to form a separate 

 genus, which, if the name of Strougylocciitrotiis is to be restricted to the above nanied species, must 

 get the name of Eiiryccliiiiiis Verrill'). As long as we have no sufficient knowledge of the species 

 that has to be called Strongylocentrotus^ viz. chlorocentrotus Er., it will be most correct to call all the 

 species mentioned here Strongylocentrotits^ and leave the name of Euryccliiiiiis for disposal, if it should 

 prove to be necessary to use it. 



Strongylocenfrotus drprcssiis (Ag.). Of this species I ha\-e received a specimen from Prof. 

 Doderlein, and another specimen I have found among the Pxhinids from Japan sent me for deter- 

 mination bv Prof. d'Arcy Thompson. Accordingly I am able to give some informations of it, which 



') E. A. Verrill; Ou the Polvp.s ;iiul Corals of Panama, with descriptions of new species. Proc. Bostou Soc. Nat. 

 Hist. X. 1866. p. 340. 



The Ingolf-Expedition. IV. i. l6 



