KCHINOIDEA. I. 



125 



evident; these three species must form a separate genus which gets the name of Toxocidaris Ag. '). 

 As the first species of this genus (of which no diagnosis is given) is named T. Dclalandi Ag., which 

 is synonymous with crythrogrammus (Rev. of Ech. p. 163); thus this species becomes the type of the 

 genus Toxocidaris. Agassi z is surely right when he maintains (Rev. of Ech. p. 450) that the some- 

 what petaloid structure of the pore areas on the actinal side is no valid generic character of Toxo- 

 cidaris, but the peculiar globiferous pedicellarise leave no doubt of the correctness of the genus with 

 the limitation given here. 



As a synonym of tStfoatgylac,* tuber culatus Agassiz (Rev. of Ech. p. 165) names Anthocidaris 

 homalostoma Liitken 2 ). I am so fortunate as to be able to prove this to be incorrect The specimens 

 of Liitken are only naked tests, of which one is from China, for the others no locality is given. 

 Among the Echinids from Japan, sent me by Prof. d'Arcy Thompson, is a specimen, which with 

 regard to the structure of the test agrees so exactly with the specimens of Liitken, that there can 

 be no doubt of their being identical. So I shall here give the necessary informations of this species. 

 The specimen in hand has a diameter of 30""", and is from Yokohama Bay. The primary tubercles of 

 the ambulacral areas are almost as large as the interambulacral primary tubercles. There is an 

 irregular series of small tubercles in the middle, and a similar one outside of the primary series on 

 either side; this outer series is formed of a larger and a smaller tubercle alternately, a larger tubercle 

 being found below on each ambulacral plate, and a smaller one above; besides some small tubercles 

 are found outside the latter ones, nearer to the pores. The interambulacral areas have a double series 

 of secondary tubercles between the primary series, and one outside on either side; just at the ambitus 

 two series are found outside of the primary ones, and all these tubercles form here distinct oblique 

 series. The colour of the test is grayish green. The spines are thick, evenly tapering, the longest 

 half as long as the diameter of the test; they are of a deep violet colour. Two ocular plates reach 

 to the periproct. The pore areas are rather highly petaloid on the actinal side, and as only a few small 

 spines are found nearest to the mouth, almost only tube feet are seen here. In the lower ambulacral 

 plates only 3 pairs of pores are found, above there are 8 9 pairs. The buccal membrane contains 

 rather numerous fenestrated plates, of which some of those outside of the buccal plates are thick and 

 carry pedicellariae. The gills contain the common irregular fenestrated plates. The slits distinct The 

 globiferous pedicellariae are as in Strongyloc. drobachicnsis with well developed neck (in the specimen 

 in hand I succeeded only with much difficulty in finding one small globiferous pedicellaria). The tri- 

 dentate pedicellariae (PI. XXI. Fig. 6) resemble much the narrow form in Toxocidaris luber culatus ; but 

 also another form is found with the blade somewhat widened in the point, and with a more developed 

 net of meshes. As I have not been able to find a whole specimen of this form, I have given no 

 figure of it, so much the less as its seems that no great stress can be laid on the tridentate pedicel- 

 larise as specific characters in most of the Strongylocentrotus-\-C&.z. forms. No transverse series of small 

 teeth are found on the edge. The ophicephalous and triphyllous pedicellarise of the common form. 

 The spicules of the tube feet are very characteristic (PI. XXI. Fig. 30), biacerate, a little curved, 

 generally with a rather strong point in the middle of the outer side. 



') List of Echinoderins etc. Bull. Mus. Coinp. Zool. I. p. 22. 

 2 ) Bidrag til Kundskab om Echiniderne. p. 96. 



