MUSEUM OF COMPARATIVE ZOOLOGY. 109 
The young were taken from the adult by cutting off the disk, leaving 
the arms intact. By removing the disk in this way it was found that . 
the young remained in it, and when left for a short time in pure 
water the older specimens crawled into view. Lyman* has recorded 
that adults found near Bordeaux often in confinement voluntarily cast 
their disk, from which the orange-colored young emerge. ‘The older 
forms of the young can voluntarily escape from the disk through the 
genital slits.) Those which have an umbilical attachment, particularly 
the bilateral larve, must be teased from the ovarian attachment by 
means of needles or small scalpels when required for study. A deli- 
cate dissection is necessary to separate the larva from the inner wall of 
the body without harm to the attached young. 
The larve were studied alive. Many were killed in weak alcohol, 
hardened in 93° alcohol, placed in chloroform for three minutes, and 
then mounted in Canada balsam. The treatment with chloroform 
brought out the plates with success. Staining in borax carmine showed 
the water-tubes, but obscured the plates. 
Young Amphiure were found from the’ first of August until the end 
of September, with little reduction in numbers except in the last week. 
The number of young from different adults varied. Ordinarily a gravid 
adult would have from ten to fifteen (generally ten) free young, and 
possibly several bilateral larvae at the same time. The older young live 
free in the body cavity, generally with the arms coiled up, but often 
with an arm extended through the genital slit. Parturition is moder- 
ately slow, sometimes rapid. The young when born are orange-colored 
on the disk, with whitish-colored arms, and with plates less firmly 
articulated than in the adult. When once born, young were not seen to 
return to the pouches, nor were they cared for by the adult. They did 
not cling to the mother after birth. Especial attention was directed to 
this observation, for I was familiar with the figures given by Thomson f of 
young Ophiurans of another genus clinging to the disk of the adult. 
The young Amphiure which voluntarily left the parent were of course 
* Op. cit., p. 123. 
+ Notice of some Peculiarities in the Mode of Propagation of certain Echino- 
derms of the South Sea, Journ. Linn. Soc., XIII. Dr. W. Stimpson (Proc. Bost. 
Soc. Nat. Hist., 1V. p. 226) found in Charleston, S. C., small Ophiurans clinging 
to the arms of Hemipholis cordata, Lym. (Ophiolepis elongata, Say). He regarded 
them as the young of the animal to which they were clinging, and thought that they 
*‘correspond”’ to the genus ‘‘ Ophionyx, M. T.” 
Lyman (Challenger Ophiuroidea, p. 157) describes and figures two stages of the 
young Hemipholis which he finds clinging to the arms and disk, and “‘ suspects” 
that the genus is viviparous. 
