171 
on the tubercles. The genital plates carry one larger tubercle 
near the inner edge; genital pores only beginning to develop, dis¬ 
tinet only in one of the plates. Ocular pores indiscernible; Ocular 
I is broadly insert. The central plate is smooth, fairly large. Hardly 
a single miliary tubercle to be observed on the whole apical system 
(Fig. 17). The buccal plates carry a number of ophicephalous ped- 
icellariæ (probably also triphyllous; this cannot be ascertained de- 
finitely, most of these pedicellariæ having been rubbed off. 1 ) 
17. 
Fig. 16. Apical system of Ps. variegatus. 15 /i. 
Fig. 17. Apical system of Ps. grossularia. 9 /i. 
Regarding the pedicellariæ I may refer to the description and 
figures given in the „Siam-Echinoidea\ No tridentate pedicellariæ 
are found in the type specimen. The tubefeet contain fairly numer- 
ous bihamate spicules. 
It is easily seen that this species is nearly related to Pseud- 
echinus Huttoni, with which it agrees especially in the colour of 
test and spines. That it is, however, a distinet species is evident 
enough. It differs from Huttoni in its nearly globular shape and 
in the scarcer tuberculation; further, the apical system is different, 
the genital plates being more bare than in Huttoni. Also the faet 
that genital pores have not yet been formed at a size of 20 mm 
h. d., while in Huttoni they are developed already in specimens 
of only 15 mm h. d., is a noteworthy difference. And then ihe 
faet that Huttoni is known only from the seas off the South Is- 
') This feature also conspicuously distinguishes this form from Ambly- 
pneustes, in which (— as also in Holopneustes —) upon the whole 
nothing but the buccal tubefeet is found on the buccal plates and on 
the peristomial membrane. 
