ECHIN EA. II. 25 



larger form of tridentate pedicellariae. In Ph. hispidum I have found a kind of ophicephalous pedi- 

 cellaria; this ma\ suggest that ophicephalous pedicellarise will prove to exist also in the other species 

 of the genus Echinosoma. Agassi z is then evidently right in making panamenst an ally of /%.» 

 tenue, whereas it is certainly less fortunate to make Ph. hispidum, the Pacific representative of the 

 Caribbean and Northern Atlantic Ph. uranus , as by the latter is probably meant not the true Echi- 

 nosoma annuls, which is not known from the Caribbean Sea, but the Hygrosoma Petersii, which has 

 hitherto been wrongly called Phormosoma 11 mints. — Regarding the new species Phormosoma, zealandi® 

 A. Ag., established on a specimen from the Challenger St. 169, identified as Asthenosoma gracilet , 

 it is impossible to state with certainty to which genus it really belongs, since not a word is said about 

 the spines and pedicellaria;; to judge from the figure given of an ambulacrum (PL 51. Fig. 3) it may be 

 supposed to be likewise an Echinosoma, which would be in accordance with the statement (p. 108) that 

 it is allied to Ph. hispidum. 



Professors Bell, de Loriol and Lambert besides Professor Agassi z have also opposed 

 my classificatory results. Professor de Loriol only remarks regarding the genus Pseudechinus es- 

 tablished by me for Echinus albocinctus Hutton, that he thinks que e'est aller 1111 pen loin que de 

 creer une coupe nouvelle basee sur ce seul et unique caractere let encore faudrait-il s'assurer qu'il est 

 parfaitement constant), qui ne peut s'observer que sur les exemplaires dont le revetement est eutiere- 

 ment conserve '. As Professor Doderlein has already (op. cit. p. 231— 3) carefully answered these objec- 

 tions, I need only refer to his remarks on the question with which I quite agree. I may however make 

 the more general remark that in the Families Echinidts, Toxopneustidm and Echinometrida, the structure 

 of the test is upon the whole very similar, so much so indeed, that it seems impossible in the test 

 alone to find reliable characters even of the families, as is well seen by the manner in which forms of 

 all three families were put together in the genera Echinus and Strongylocentrotus, before the charac- 

 ters of the pedicellariae and spicules were taken into consideration. It almost looks as if, on reaching 

 the high level of development of these forms, nature could not go any farther on those lines, (the 

 EchinometridcB, of course, form a remarkable exception), and, instead, went on to develop the pedicel- 

 laria;, especiallv the globiferous, into very characteristic structures. Be that as it may; everybody who 

 has studied a large number of the genera and species of these three families, with regard also to 

 their pedicellariae and spicules, must be struck with the remarkable constancy and characteristic appear- 

 ance of these organs and find it very natural to make them the foundation of the classification, in 

 spite of their being so small that they cannot be seen without careful microscopical examination. — 



De Loriol's remarks (op. cit. p. 16) on my limitation of the genus Sterechinus as well as those 

 of Professor Doderlein (loc. cit), I cannot answer before I have undertaken a renewed study of this 

 whole group, which I intend to do in my Reports of the Swedish and the German South-Polar Ex- 

 peditions. 



Professor Bell in his Report on the Echinoidea from South-Africa- most decidedly keeps aloof 

 from my classification, without giving, however, very definite objections. To his remark that he does 



1 Notes pour servir a l'etude des Echinodennes. II. Ser. Fasc. II. 1904. p. 20. 

 Marine Investigations in South Africa. Vol. III. 1904. The Echinodenna. Part I. Echinoidea. 



The Ingolf-Expedition. [V 2. 4 



