97 



by comparing it with the figures given here, very bad. — The buccal membrane 

 contains the usual ring of plates in the oral edge; otherwise no plates, but some 

 bihamate spicules are found. In the tubefeet spicules (bihamate) are very scarce. 

 The spines have no central thorn in the point; they are not swollen. In larger 

 specimens the pores are rather distant from the edge of the area. 



In his most severe (but not too severe) criticism of Perrier's work on the 

 pedicellariæ (Rev. of Ech. p. 661) Agassiz says: „no mention even is made of 

 Grube's suggestions as to the pedicellariæ of these interesting genera" (Temnopleurus, 

 Salmacis etc.). The only thing I can find in the writings of Grube concerning the 

 pedicellariæ of Temnopleurids is the following notice: „Bei der Gattung Mespilia 

 sind auf der Rückenseite die Mittelpartien der Ambulacral- und Interambulacral- 

 felder stachelfrei und erscheinen bei trocknen Schalen wie fein chagrinirt; bei wohl- 

 erhaltenen Weingeistexemplaren sehen die Stellen so aus, als wären sie mit Filz 

 oder Schimmel bekleidet, und die mikroskopische Untersuchung dieses Überzuges 

 zeigt, dass derselbe aus lauter Pedicellarien von der Form der gemmatce besteht, 

 während Pedicellarien mit schlanken Armen spärlicher zwischen den Stacheln vor- 

 kommen" '). According to the manner in which Agassiz expresses the fact of the 

 omission it can scarcely be this little notice which is meant. I am sorry to be 

 ignorant of something of importance regarding the pedicellariæ; but it is very un- 

 fortunate that Agassiz so very often refers to his own and other authors writings 

 without citing the place or even the work in which the observations are found. 

 It causes his fellow workers very much unnecessary and, unfortunately, often lost 

 labour to find out the references. 



Mespilia Whitmœi BelP) does not differ from globulus as regards pedicellariæ 

 and spines (I have examined the type-specimen). As distinguishing characters are 

 pointed out by Bell the well-marked gill-cuts, the narrow median ambulacral space 

 and more numerous tubercles, and the more spatulate character of the free end of 

 the radius. None of these characters are reliable. Two specimens (from „the 

 South-Sea", 20 — 25 mm. in diameter) preserved in the Museum of Copenhagen, 

 which are quite similar to the type-specimen of M. Whitmœi, have a very narrow 

 median bare space in the ambulacra and more tubercles than usual, but the actinal 

 cuts are small. The character in the radius (rotula) is scarcely of any value either; 

 in one specimen I find two of the rotulæ spatulate, the three others distinctly 

 bifid. Upon the whole I do not find the form of these inner structures (auriculæ, 

 dental apparatus) so constant as to be relied upon for specific characters. When 

 Bell says that the number of pores of the outer row „seems to be about 



') Über diejenigen Gattungen der regelmässigen Seeigel, welclie an den Grenzen der Täfelchen so- 

 wohl auf den Ambulacral- als Interambulacralfeldern Eindrücke zeigen. Jahresber. Schles. Gesellsch.' 

 Vaterl. Cultur. XLlIl. 1865. p. 62. 



'') Description of a new species of the genus Mespilia. Proc. Zool. Soc. 1881. p. 433. 



I). K. n. ViclensI;. Splsk. Slir., 7. ]ln-kl,e. n;iluivi(leTKk. nn inatlicm. AM. 1. 1. 13 



