102 THe Ottawa NATURALIST. [August 
glass in order to force fluid through the pores, or to squeeze the 
yolk-ball out of its central position ; but neither experiment suc- 
ceeded, and the capsule repeatedly burst. The yolk poured out 
as a granular fluid, orange or ochre in tint by transmitted light, 
and destitute of the large spherules, which Claparede described in 
his mites’ ova. Thus the capsule does not appear to be minutely 
perforated and no space seems to exist inside the shell, or, if it 
exist, it must be filled by some dense clear substance of which I 
saw no indication in ruptured eggs. I think that no space exists, 
and that the apparent space, around the central yolk-ball, is due 
to the great thickness of the external capsule. Clapareéde, I may 
add, speci-lly refers to a space filled with clear fluid, which he 
considered had entered through the shell from the surrounding 
water. 
To summarise these points, it may be said that the ovum of 
fydrachna consists of an opaque globular vitellus, bright red in 
‘colour, consisting of minute yolk granules and germinal proto- 
plasm; surrounding this ball is a thin skin or pellicle, and enclos- 
ing the whole is a thick horny chorion or shell, dotted all over 
with external granular projections, but whether or not pierced by 
radial canals, or pores, is uncertain. Embryonic development 
appears to be slow, and I caunot in this note give any details, but, 
like all the spider and mite class, there is no true larvai metamor- 
phosis, the newly hatched young resembling, in all essential fea- 
tures, the adult, save for the possession of six instead of eight 
legs. I have constantly found one of the specimens of Hydrachna 
ensconced near the masses of eggs, as though keeping watch over 
them. Many spiders show parental care, but I could not decide 
whether Hydrachna exhibited such guardianship or whether the 
scarlet eggs proved attractive merely on account of their bright 
colour. The body of Hydrachna, about the size of a large pellet, 
is of a rude oval form, the integument is smooth, soft, and deeply 
creased with irregular folds. Owing to its ceaselessly active, 
movements, the animal is difficult to study ia life, the long attenu- 
ated snout being protruded and withdrawn, and the whole body 
changing shape as though it were a bag of soft jelly. The eight 
legs (not six as in insects) have a thick fringe of hairs on the 
Sa a ae 
