41 
“ On some un described Hairs in Copepoda,” by the same. 
These hairs are very simple in form and so minute that 
they can only be glimpsed with the objective. They are 
planted in depressions of the integument and are circular in 
section, the basal part thicker and tapered towards the 
middle (what is termed biscuit-shaped by the German his- 
tologists), the terminal part longer and ciliiform. Their im- 
portance is shown by their constancy in position, and by the 
bilateral symmetry of their distribution. They are found 
on both the dorsal and ventral surfaces of the abdomen, but 
I have only succeeded in seeing them on the dorsal surface 
of the cephalo-thorax, where they are most numerous in the 
frontal region. The pair on the tergum of the last abdomi- 
nal segment are easiest to find ; and it was after seeing these 
that I looked for them elsewhere. I have found them in 
both Cyclops and Canthocamptus, belonging to distinct fami- 
lies, whence I conjecture that their presence may be general 
in the order. Similar hairs implanted in pits have long 
since been demonstrated in Insecta, and possibly add to the 
delicacy of touch required by flying and swimming animals 
to enable them to thread their way through obstacles. 
“ On an Undescribed Acinetan,” by the same. 
The animal in question was found on the ventral surface 
of Cyclops gigas (especially females), on and about the bases 
of the oral appendages. In size it comes near Podophrya 
Cyclopis and is similarly attached by a short rigid pedicel ; 
but its form is usually much less distinctly spherical, un- 
dergoing slow irregular changes. The body is invested in a 
cuticle and the endosarc is usually full of reddish brown 
granules. The nucleus is spherical, like the solitary con- 
tractile vesicle which in one specimen was found to contract 
at intervals of from SV to 44". The tentacles, which are 
the distinguishing feature, are much thicker than in an 
ordinary Podophrya, rounded, obtuse, and quite undilated 
at the summit, a little below which a circular constriction 
is seen. No other trace of organization is to be made out 
in them when the animal is quiescent. After slightly press- 
