ME. P. H. CAEPENTER ON THE &ENTJS ACTINOMETEA. 73 



described by Goldfuss \ of wbicli neitber be nor any subsequent observer lias given a 

 satisfactory explanation ^. 



Glenotremites was at first placed by Goldfuss among tbe JEchmoklea, and was sup- 

 posed by bim to bave some relatiousbip witb tbe Cidarklce. It is a somewbat bemi- 

 spberieal body, in tbe centre of tbe flattened upper surface of wbicb is a large round 

 opening, called by Goldfuss tbe moutb. " Urn den Muud liegen fiinf grosse ovale Locber 

 und zwiscben diesen fiinf fiacbe Rinnen, die sicb bis zum Rande erstreckcn, wo ibre 

 Vertiefung nicbt ausltiuft, sondern durcb. einen erhabenen Saum begranzt wird 



Die Locber gebeu tricbterformig in die Tiefe ; die B^innen sind die Eelder der Eiibler- 

 gange." Tbese grooves were supposed by Goldfuss to be perforated by minute pores for 

 tbe passage of tentacles. 



Tbe convex dorsal side of tbe body bears numerous sockets for tbe attachment of 

 cirrbi ; but Goldfuss compared tbese at first to tbe large tubercles of tbe Cidaridce. At 

 tbe apex are five smaller apertures ; and Goldfuss suggested tbat these might be respi- 

 ratory and the others genital, or, more probably, that both, like the cirrhus-sockets, 

 marked the points of attachment of various kinds of spines. Subsequently, however, in 

 bis description of a second species, G. couoldeus, be spoke of the larger apertures as 

 ovarian openings, and recognized the resemblance between the sockets on the convex 

 surface and tbe similar ones on the dorsal surface of the centrodorsal piece of Comatula 

 to which the cirrbi are articulated ; and he suggested tbat Glenotremites might be more 

 nearly related to the Comatulidce than to the Bohinidce, as be had at first thought. 

 Agassiz ^ adopted this view, and placed Glenotremites among the Crinoids, and near to 

 Comatula. Like Goldfuss, be regarded the central aperture as a moutb ; but tbe five 

 punctated grooves radiating from it, which were supposed by Goldfuss to be provided 

 with tentacles, were regarded by Agassiz as the points of insertion of the radii. He did 

 not attempt to explain tbe five large openings on the ventral surface and the five smaller 

 apical ones. Eoemer*, who, like all subsequent writers, accepted the view that 

 Glenotremites is the centrodorsal piece of a Grinoid allied to Comatula, regarded tbe 

 former as " trichterformigen Arm-Anfangen oder Mund-Winkeln," but did not under- 

 stand those of the dorsal surface. 



D'Orbigny ', who confused Glenotremites with Comaster and Solanocrinus under one 

 name, Comatula, and Pictet ^ who retained it as a separate genus, did not attempt to 

 offer any further explanation of its peculiarities, and, so far as I know, Agassiz and 

 Eoemer's views have been generally accepted. 



' Pelref. German, i. p. 159, Taf. slix. fig. 9, Taf. U. fig. 1, and ii. p. 186, Taf. clx. fig. 18. 



= The following section was -WTitten early in 1877, and was in the hands of the Secretary of the Linnean Society 

 in June of that year. The substance of a portion of it was referred to in my paper on Pentaerinux and lihizoa-iaus 

 (' Journal of Anatomy and Physiology,' Oct. 1877, p. -15). I am therefore exceedingly glad to find, from a paper 

 published early in 187S ("Ueber einige astylidc Crinoiden," Zeitschrift der dcutsohcn geologischen Gescllschaf t, Jahr- 

 gang 1 878, p. ;33), that Schliiter has independently given the same explanation of Glenotremites as had occurred to 

 myself. I learn from his paper that even as late as 1871 Goldfuss'e original views were still held by Geinitz (Elb- 

 thalgebirgo, i. 1871, p. 91). 



^ Prodrome, loc. eii. p. 289. ■* Letha;a Geognostica, v. p. 177. 



* Cours elumeataire, ii. p. 138. « Iraite de Palcontologic, iv. p. 290. 



