6o 



TH. MORTENSEN, 



(Schwed. Siidpolar-Epx. 



it does not even seem possible to maintain it as a distinct variety of L. albus. (I 

 may state that I have examined the type specimens of bullatus in the British Mu- 

 seum.) 



Besides the Strongylocentrotus bullatus Prof. Bell mentions in the place quoted 

 a ^Strongylocentrotus sp. inc.-> (p. 89. PI. VIII. figs. 3, 4). As there is nothing in 

 the description or the figures which might indicate that to be another species, I can- 

 not doubt that it is likewise L. albus. (I have not examined this specimen myself.) 



In the ^Challengers-Echinoidea p. 106 Prof. AGASSIZ records Strongylocentrotus 

 gibbosus from Stat. 304. Relying on this determination I referred in the »Ingolf»- 

 Echinoidea I. (p. 123) the species gibbosus to the genus Loxechinus, finding the 

 pedicellaria; of the >Challengen specimen quite like those of L. albus. The exami- 

 nation of the type specimen of gibbosus, however, proved that this species has no- 

 thing to do with the genus Loxechinus. There ran then scarcely be any doubt that 

 the ^Strongylocentrotus gibbosus^ from the ^Challengers Stat. 304 is really Loxechi- 

 nus albus (cf. Tngolf) Echinoidea. I. p. 178). 



From the critical remarks given above it seems evident that the South Amer- 

 ican Coast, from the La Plata River to Peru is inhabited only by the following 

 littoral species of the Echinina: Notechinus magellanicus, Sterechinus Neumayeri, 

 St. Agassizii, Loxechinus albus and Toxocidaris gibbosus. — PHILIPPI, in his paper 

 Tiber die chilenischen Seeigek (Verb. d. deutschen wiss. Vereines zu Santiago. 

 Chile. II. 1892, p. 247) records the following >Echiniden im engeren Sinn»: Helio- 

 cidaris alba Mol., H. antarctica Ph., H. erythrogramma Dech. (sic!), Echinus 

 Cunninghami Ph., rodula Ph., lepidus Ph. and magellanicus Ph. — The names 

 Helioc. antarctica, Echinus Cunninghami, rodula and lepidus are, evidently, only 

 nomina nuda. The first of them is supposed by Philtppi himself to be a variety 

 only of T>Heliocidaris alba^, and for the three latter it will probably not be too 

 rash to suggest that they will prove to be identical with the Sterechinus species 

 or Notechinus magellanicus. In any case it is somewhat surprising to have nomina 

 nuda introduced into literature at so late an epoch.* 



* The reproach of having introduced nomina nuda into the literature is raised against myself by 

 Lambert & Thiery (Notes Echinologiques. I. Sur le genre Cidaris. Bull. Soc. Sc. Nat. Haute Marne. 

 VI. 1909, p. 20), because I have preliminarily characterized some species by the pedicellariae alone. As 

 Lambert & Thiery wholly reject the pedicellaria, as being of no classificatory importance at all (because 

 they are generally not to be found in the fossil forms), their conclusion as regards such species is, thus far, 

 correct. In reality the structural features of the pedicellarine described and figured by me for such species 

 {Schizocidaris assimilis e. g.) are so characteristic that the species is easily recognizable thereby; and as 

 regards Schizocidaris assimilis, the species objected to, I may recall the fact that several other characteristic 

 features are pointed out (Ingolf Ech. I. p. 25). But, of course, I agree that it is highly necessary that all such 

 species should be completely described as soon as possible. (Cf. the Introduction of my paper >On some 

 West Indian Echini>. Bull. U. S. Nat. Mu's. 1910). 



