ON PENNELLA BALANOPTERZ. A27 
to contain a quantity of minute fatty particles, the products of degeneration. It 
should be remembered that the parasites were taken in the autumn, after they had, in 
all probability, shed a crop of ova, and before the next crop was ripe for impregnation. 
THe MALE. 
It is well known that in the parasitic Copepoda the male is insignificant in size 
as compared with the female. In Chondracanthus and some other genera it has been 
ascertained that the male is attached to the female, close to the apertures for the 
ova strings. I consequently made a close examination of the ventral surface of the 
body of all my specimens of Pennella, with the object of observing if a male were 
present in any of them, but I failed to recognise one. Koren and DanNrIELSSEN 
stated definitely in their memoir on P. balenoptere that they had not seen any 
males attached to their specimens, so that the male of P. balenopterx is as yet 
unknown. It would, indeed, appear that the recognition of the male in any species 
of Pennella is a rare occurrence. I have stated in the introductory section that 
Bocconz, so long ago as 1674, figured, firmly affixed to the Pennella, which is now 
regarded as P. filosa, a small object which he spoke of as a “‘pediculus” or louse. I 
have no doubt, from its relative size and the place of attachment, that it was the male 
of the species. Boccons, therefore, should have the credit of being the first to see and 
figure a male Pennella, though he did not realise its sexual significance. In Pennella 
exoceti and in P. varians the male has also been recognised and figured. 
The habitat of the male Copepod, as in the case of Pennella, when not attached 
to the female, is uncertain. In a species like Lernwa branchialis affixed to the gills 
of the Gadidez and flounders, males have been found within the gill-chamber, some 
attached independently to the branchize, others to the bodies of the females. In 
P. balenopterx the females were affixed to the extensive surface of the smooth back 
of a great whale, to which they had doubtless attached themselves in the Cyclops phase, 
through which the female passes before she becomes adult and assumes relatively gigantic 
proportions, though in many respects retrograde characters. If the males of Pennella 
be provided with hooked antennz, like those found in the male Lernzea, as there is no 
adjoining chamber for their lodgement, they may become directly attached to the skin 
of the whale in proximity to the females, until the time arrives when they are required 
to affix themselves to the females for the purpose of fertilising the ova when these are 
ripe for impregnation. If the male Pennella, as is very probable, is insignificant in 
size, when unattached though perhaps in close proximity to the female, it would easily 
be overlooked. 
In considering the question where and when the ovarian ova are impregnated 
in the parasitic Copepoda, it has to be kept in mind that whilst the female is fixed to 
its host, the male retains for a considerable time the character of a free swimming 
Crustacean, though subsequently it affixes itselfin many of, and possibly in all, the species 
