256 MR. R. COLLETT ON BALZNOPIERA BOREALIS. — [Feb. 2, 
by myself; and upon inquiry amongst the whalers, I was in- 
formed that only Capt. Bryde has noticed such parasites on a 
single individual captured off Vardé in July. As no specimen has 
been preserved, it cannot be stated whether they were Crustaceans 
(Pennellidee?), Discophora, or other forms. ‘They were worm-like 
animals, about 50 millim. long, and were attached to the edges of both 
flukes (caudal lobes), where they formed a row of tree hanging threads. 
Some were also attached to the upper surface of the flukes. 
In a set of baleen-plates belonging to one specimen, and brought 
to the University Museum in Christiania from Sorver (Hammerfest) 
in 1883 by Dr. Guldberg, most of the plates are infested on both 
sides with innumerable specimens of Balenophilus unisetus (figs. A, 
B, C, D), a Copepodous crustacean of the subfamily Harpacticine, 
described by Aurivillius ina pamphlet published in Stockholm in 1879, 
and discovered by him on the baleen-plates of a specimen of Bale- 
noptera sibhbaldi caught at Vadso in July 1877. In 1884, Mr. A. 
Heneage Cocks found this parasite on a specimen of the same whale 
at Sérveer, near Hammerfest (‘ Zoologist,’ 1885, p. 135). So far as 
I know, it has never been found by other observers. Its occurrence on 
Balenoptera borealis is therefore of interest’. The fully developed 
specimens (figs. A, B) can only with difficulty be recognized in 
their dry state; but the larve in their Nawplius-stage (figs. C, D), 
which are attached to the plates in myriads, still retain most of their 
original form and appearance. 
These two parasites appear therefore to be of very rare occurrence. 
However, the intestines of all the specimens that 1 examined, inclu- 
ding those which 1 found on the beach, were, without exception, 
filled with thousands of Echinorhynchi, belonging to twe different 
species. 
One of these, which was very much less numerous than the other, 
seemed to resemble very closely . porrigens, Rud. Its length was 
100 millim. The rostellum was unarmed, the neck long, and the 
body formed an even continuation of the neck. As I unfortunately 
only brought one perfect specimen away with me, and as this has 
the proboscis half retracted, it cannot be decided with certainty 
whether the species is actually identical with 4. porrigens. 
The other species appeared in all the specimens examined, and in 
such vast numbers that in some places there were three or four upon 
each square inch, and they moreover thickly covered the inner coating 
of the intestines wherever an incision was made. The smallest speci- 
mens were thin, semi-transparent, and immature; their length wasabout 
10 millim., the breadth 2 millim. From these up to the full-grown 
specimens, the length of which was about 25 millim., there were all 
gradations of size. While the majority of the specimens were of a 
white colour, the fully adult were of an intense red, as if their 
integument were impregnated with the colour of the red Crustaceans, 
which are the principal food of their hosts. ‘The species to which 
it approaches nearest is LZ. brevicollis, deseribed by Malm in 1867, 
1 T sent some of the specimens to Dr. Aurivillius, and he has confirmed 
their identification with the species found on the Blue Whale (B. sibbaldi). 
a ie i oe, 
