112 



,,Teninecliinus" (Genocidaris) maculatus: „should the knob-and-socket arrangement 

 of the union of the plates be discovered , Temnechinus will enter the Temno- 

 pleurinœ". This contradiction by Duncan unfortunately has been more accentuated 

 by Ghegory, who expressly says in the diagnosis of the Glyphocyphince and Ortho- 

 lophinœ „the plates are united by dowelling", whereas this sentence is omitted in 

 the diagnosis of the Temnopleurince. The fact is just the opposite, as originally 

 shown by Duncan. To be sure all the genera without true pits have not been exa- 

 mined with respect to this structure, but it may be jusliliable to conclude from those 

 examined that in none of these genera such a dowelling exists. Of Temnechinus 

 the fact is stated above; Trigonocidaris albida and Genocidaris maculaiu have been 

 examined by Agassi/. („Blake"-Echini. p. 37) with the result that no dowelling exists» 

 and the same I can state for Hijpsiechinus. 



The genera Hypsiechinus , Prionechiniis , Genocidaris, Trigonocidaris, Temn- 

 echinus and Opechinus must then form a second subfamily: Temnechininœ. (In 

 Delage & Hérouard's „Traité de Zoologie concrète" for which work I have written 

 the classification of the regular Echinoidea, this subfamily is named Trigonocidarime. 

 It will be more convenient to name it Temnecliininœ, tlie more so, as this name lias 

 already been used by Lambert (comp, above p. 110), though perhaps not exactly in 

 the sense in which it is used here). — The genera Hypsiechinus and Prionechinus, 

 to be sure, differ considerably from the other genera, the former by its triradiate 

 spicules and its globiferous pedicellariæ (comp. „lngolf"-Echinoidea. p. 86), the latter 

 by its smooth test. It would, in fact, be very difficult to say by which characters 

 Prionechinus is distinguished from the Echinometrids. Tliere can, however, be 

 scarcely any doubt that they are both most nearly related to Trigonocidaris and Geno- 

 cidaris. — The name Glyphocyphince cannot be used for this subfamily. The genus 

 Glyphocyphus Hainie has perforate and crenulate tubercles, and the same holds good 

 for the genera Dictyopleurus Dune. & Sladen and Arachniopleurus Dune. & Sladen; 

 these genera thus cannot belong to the Temnopleuridœ, but, jirobably, form a spe- 

 cial group of the Diadematids, distinguished by the ornamentation of the test. The 

 name Glyphocyphince may be retained for this group. The ambulacral structure of 

 Arachniopleurus is not sufficiently known, but from the perforate tubercles it may 

 be concluded that it will prove to be diadematoid; in Glyphocyphus the ambu- 

 lacral plates are composed of low, broad primaries, with straight transverse sutures, 

 and in Dictyopleurus they are of true diadematoid structure. The genus Ortholophus 

 Dune, seems really to be related to Trigonocidaris, but I should prefer not to name 

 the subfamily after a little known fossil form, whose relation to the recent genera 

 is not beyond doubt. The name „Ortholophinœ" then ought not to be used. — 

 Among the other fossil genera referred by Duncan to the Temnopleurids Zeuglo- 

 pleurus Greg, has diadematoid ambulacra, and the same may be the case with 

 Echinocyphus Coll. and Leiocyphus Cott., which thus cannot remain here, whereas 



