57 



course, does not alter the classificatory value of the pedicellariæ in the other 

 regular Echinids; but we are forced to seek the generic characters of the Temno- 

 pleurids in the structuie of the test. (The spicules do not yield such characters 

 either; they are, with the single exception of Temnopleurus Reevesii, simply biha- 

 mateV Now, fortunately, the Temnopleurids afford many very characteristic fea- 

 tures in the test, and as these have been very well studied by the previous authors 

 on this subject, the classification of these forms is very well founded, and I have 

 almost nothing to alter with regard to the genera. As for the species the pedicel- 

 lariæ often alTord excellent characters, and thus, naturally, a close examination of 

 these structures makes some rearrangement of the species necessary. 



All the usual four kinds of pedicellariæ occur in the Temnopleurids '). The 

 tridentate ones have not been found in all the species, thus f. i. in several of the 

 P/eurecftmus-species. They do not vary much in form, but afford, however, good 

 specific characters in a lew instances (the Sa/macis-species). The globiferous pedi- 

 cellariæ are always w'ilhout neck, and they have always (? Amblypneustes grossiilaria) 

 two quite separate glands on each valve; the stalk is composed of long fibres as 

 in the Echinidce. As is said above, they occur in all the forms found in the Echi- 

 nidœ, Toxopneiistidœ and Echinometridœ. The primitive form known from Par- 

 echinus and Loxechinus is found among the Temnopleurids only in Hypsiechinus, 

 which is evidently the most primitive of all the Temnopleiiridœ , as indicated 

 also by its triradiate spicules. The globiferous pedicellariæ of Mespilia (PI. VII. 

 Fig. 16, 22) remind one somewhat of this form, but they are evidently rather modi- 

 fied. — The form characteristic of Echinus is found in some species of Salmacis 

 and Temnopleurus, {Salni. sphœroides, dussumieri, Temnopl. toreumaticus); the form 

 without lateral teeth characteristic of the Toxopneustidœ, is found in Salm. uirgulata 

 and bicolor, Pleurechinus uaricr/atus etc. The most common form, however, is that 

 with one unpaired lateral tooth, the Echinometrid-form; it occurs in Salm. bicolor 

 and belli (together with the form without lateral teeth), Pleurechinus Döderleini, 

 Amblypneustes etc. The ophicephalous and triphyllous pedicellariæ do not present 

 any marked peculiarities: the latter are never serrate in the outer edge, except in 

 Prionechinus and Trigonocidaris. The sphæridiæ do not present any peculiar fea- 

 tures. — The spicules are bihamate, with the exception only of Hypsiechinus and 

 Temnopleurus Reevesii, in which latter species they are bowshaped, the ends not 

 being bent inwards. They are mostly very scarce and very delicate. 



Specific characters of importance are also found in the spines, especially in 

 the form of the point. It may be knoblike, smooth, or it may form a long central 



') Di'NCAN in his paper „On some Points in the Anatomy of the Temnopleuridæ" Ann. N. Hist. 

 6. Ser. I. 1888) gives a description of the pedicellariæ of Temnopleurus p. 128) which is very confused. 

 His .,common tridactj'le pedicellariæ" are the globiferous ones, and they have not „often" lony, soft 

 necks. „The globiferæ' are ophicephalous and tlie figure given of a „triphylta or ophicephalous" pedi- 

 cellaria looks more like a small ophieeplialous one. 



D. K. D Vidensk- Selsk-Skr-, 7. Række, natui-viileiisk. (ifï malheni. Aid. I. 1. 8 



