I2 8 ECHINOIDEA. I. 



No transverse series of small teeth. The ophicephalous and triphyllous pedicellariae without conspicuous 

 peculiarities. The spicules of the globiferous pedicellariae are bihamate, those of the tube feet of a 

 very peculiar form: biacerate, a little arcuate, with two small, axe-shaped projections on the concave 

 side (PL XXI. Fig. 32). — Parasalcnia Pohlii Pfeffer (314) I have not seen. 



In « Revision of Echini? p. 423 the family Echinometradce is defined as having always more 

 than three pairs of pores to each arc-: nevertheless Parasalcnia is also referred to this family, 

 although it has only three pairs of pores in each arc. Setting aside this contradiction is must be 

 admitted that when only the form and habitus of the test is taken into consideration by the deter- 

 mination of the relationship of the Echinids, Parasalcnia must be regarded as an oligopore Echino- 

 metrid. The examination of its pedicellariae and spicules show, however, that it has no nearer relation 

 with the Echinometrids. The spicules remind most of those in Anthocidaris, but are, nevertheless, 

 very different also from these; also the globiferous pedicellariae recall those of Anthocidaris, but are 

 distinguished from these by having no neck. Thus it is not too closely allied to Anthocidaris, but 

 it does not seem possible, at all events at present, to point out any nearer relation. That the struc- 

 ture of the spines is very different from that of the Echinometra-spines (Mackintosh 265, Stewart 

 381) is a further proof that Parasalcnia has nothing to do with Echinometra; now, to be sure, we 

 cannot lay any great stress on some difference in the structure of the spines, when this character is 

 standing alone; but when, as in Parasalcnia, it is added to other characters of more significance, it 

 will also get some importance. 



After it has been pointed out that Parasalcnia is no Echinometrid, this form becomes of con- 

 siderable interest as proving a parallel development within two different families. 



Echinostrcphus molar c (Blv.). Also this peculiar form is well known, especially Stewart (381) 

 has figured its pedicellariae with the exception of the triphyllous ones; accordingly only the most 

 important features are to be briefly mentioned here. A primary tubercle is found on all the ambu- 

 lacral plates; all the ocular plates are shut off from the periproct. The buccal membrane with rather 

 numerous fenestrated plates, not only opposite to the ambulacra (Rev. of Ech. p. 457); most of them 

 are thick and carry pedicellariae. No spines on the buccal plates; the gills with the usual irregular 

 fenestrated plates. The globiferous pedicellariae as in Echinometra with one large, unpaired lateral 

 tooth. There is no neck; whether glands are found on the stalk could not be decided with certainty, 

 as the examined specimen is a dried one. In the tridentate pedicellariae the blade is widened in a 

 somewhat spoon-shaped manner, rather strongly serrate in the edge in the outer part, without trans- 

 verse series of small teeth; only a little developed net of meshes. The ophicephalous and triphyllous 

 pedicellariae of the common form. The stalk of the pedicellariae compact. The spicules of tube feet 

 and pedicellariae bihamate. — Although this genus has most frequently trigeminate pores, it is also 

 referred to Echinometrado' in < Rev. of Ech. ; this is no doubt correct, both spicules and pedicellariae 

 being as in Echinometra. — Ech. pentagonus Yoshiw. (449) not examined. 



To the genus Echinometra are referred the species: Incuntcr (L.) 1 ), oblonga (Blv.), Mathcsi (Blv.), 



') Loven (252. p. 153) has definitivety shown the common Westindiau Echinometra to be the Echinus lucunter of 

 Linne; thus that species must keep the name, and the name of E.subangularis (Leske) used by Agassiz (Rev. of Ech.) must 

 be rejected. The species from the Pacific for which Agassiz unjustly reserves the name of lucunter, must give up this name, and 

 in future be called Echinometra Mathcei (Blv.), which name thus, according to Agassiz (Rev. p. 115), becomes the older one. 



