DEVELOPMENT OF AX APODOUS HOLOTHURIAX 
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are apt to fade and the specimens may become entirely bleached. 
The calcareous deposits in the skin are of two kinds; the six- 
spoked wheels, usually about .12 mm. in diameter, characteristic 
of the genus, which are collected in the wheel-papillae, referred to 
above; and small, somewhat flattened, curved rods with enlarged 
and often slighth" branched ends, which are about .05 mm. long 
and are scattered all through the interanibulacra. 
The habitat of this little holothurian, so far as my experience 
goes, is always coral sand, in shallow water, just inside a reef ex- 
posed to surf. Here, under a slab of rock or some shnilar shelter, 
it finds a congenial home and often (especially in Bermuda) a num- 
ber of specimens will be found occupying the limited area beneath 
a single rock. In Jamaica, the companions of Chiridota, in such 
a spot, are the two little echini, Brissus unicolor and Echinoneus 
semilunaris, and occasionally a small synaptid; but in Bermuda, 
the usual companion is Leptosynapta roseola. C'hiridota is not 
hardy, and specimens brought into the laboratory at Port Antonio 
lived but a few hours and were never very active. Curiously 
enough the pentactula larvae were much more hardy than the 
adults, for they lived more than twenty-four hours after removal 
from the body of the mother, and showed no effect from solutions 
of magnesium sulphate which completely narcotized the adults. 
Owing to their sensitiveness to changed conditions, observa- 
tions on the Chiridotas in the laboratory yielded no facts of inter- 
est. We can only assume that fertilization of the eggs and the 
birth of the young take place as in Synaptula; the study of pre- 
served material has thrown no light on these points. Specimens 
collected in Bennuda in April, and in Jamaica in July and August, 
contain young in various stages of development, but whether 
breeding occurs all the year, as seems to be the case in Synaptula 
hydriformis, is not proven. In every specimen examined which 
contained young, these were all of approximately the same stage 
of development, indicating their origin from a single ripening of 
ova. Xo evidence of two or more overlapping broods, such as 
occur in full-grown synaptulas, has been found. The number of 
young is commonly much greater than in Synaptula, for while 
small Chiridotas may contain only a few larvae, the full grown 
