Some Notes on the Hawaiian Monk Seal 
Judith E. King 1 and R. J. Harrison 2 
Up to 1958 the collections of the British Mu- 
seum (Natural History) possessed neither skel- 
etal material nor skin of the Hawaiian or Laysan 
monk seal, Monachus schauinslandi Matschie 
1905. Indeed the only remains of this animal in 
Europe until now have been those brought back 
by Dr. Schauinsland, amongst which was the 
skull of the seal later named after him by Mat- 
schie (Matschie, 1905). The stuffed skin of 
this animal is in the Bremen Museum and the 
type skull is in the Zoological Museum in Ber- 
lin, no. 32795 (Wahlert, 1956). So it was with 
great pleasure that we received, in the summer 
of 1958, through the kindness of Mr. Vernon E. 
Brock, then director of the Territorial Division 
of Fish and Game, Honolulu, Hawaii, a young 
male monk seal from Laysan Island that had 
been shipped complete and frozen to this coun- 
try. The animal was thawed, injected with col- 
oured gelatin in the vascular system, and dis- 
sected after fixation, but unfortunately the tis- 
sues were too poorly preserved for any accurate 
histology. 
DESCRIPTION 
The seal is young, has a nose-to-tail length of 
163.5 cm. (5 ft. 6 in.) and weighs 74.4 kg. (164 
lb.) complete. Kenyon and Rice (1959) give 
the estimated weights of recently weaned pups 
as from 95-160 lb. The present animal was 
caught June 4, 1958, and as it must have been 
very near to being weaned, its probable date of 
birth must have been about April 30. Although 
the weight is a little high for a recently weaned 
pup, the animal is in very good condition and 
is unlikely to have been a yearling, as yearlings 
are relatively thin and do not reach the weight 
and condition of pups that have been feeding 
from their mothers. Similarly the state of the 
epiphyses and the obvious youth of the skeleton 
make it unlikely that it is from a 2 -year-old 
animal. The age of the present animal is there- 
fore estimated to be about 5 weeks ( the thymus 
is large and weighs 32.5 g. ). The coat is dark 
1 British Museum (Natural History). 
2 London Hospital Medical College. Manuscript re- 
ceived January 15, I960. 
silvery grey dorsally, on the top of the head, on 
both sides of the fore and hind flippers, and 
on the dorsal surface of the tail. Laterally the 
grey shades to silvery white ventrally. The hind 
flippers are a little lighter grey on the inner 
side towards their insertion. There are also 
lighter patches round the eyes and surrounding 
the insertion of the supraorbital vibrissae, and 
along the upper lip. The lower jaw is light in 
colour. On the back the hairs are dark grey 
with a white tip. This white tip becomes longer 
towards the belly so that the ventral hairs are 
white with a short dark base. The moustachial 
whiskers are in five rows on each side of the 
nose, the upper row having four whiskers and 
the other rows approximately nine in each. The 
whiskers are dark brown at the base, shading to 
straw colour at the tip; they are oval in cross 
section and are not beaded as in Phoca (Fig. 
1 ). 
The tongue has a notch in its anterior end. 
The length of the small intestine is approxi- 
mately 57 ft. The only food remains in the 
stomach are fish bones and skin and these have 
been identified as being most probably from 
the puffer fish, Arothron meleagris (Lac.), 
which is a poor swimmer usually found near 
coral formations. Nematodes, a small cephalopod 
beak, and an isopod are also present in the stom- 
ach. The nematodes have been identified as 
Contracaecum turgidum, a species previously 
described from this seal, and the isopod as 
Livoneca sp., usually found as an ectoparasite 
on fish and probably ingested attached to a fish. 
In the small intestine there are remains of a 
tapeworm. It is not in a sufficiently good con- 
dition to be identified exactly, but is probably 
Diphyllobothrium sp. 
The skin and skeleton of this seal are in the 
collections of the British Museum (Natural His- 
tory), the registered number of the skin being 
58.521, and that of the skeleton 1958.11.26.1. 
OSTEOLOGY 
The skeleton of M. schauinslandi has not pre- 
viously been described and although it is at- 
tempted here to fill this gap the description and 
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