SEAL-EMBRYOS. 3 
a 
Tt will be seen that all these embryos, the place of capture of which is stated, were 
obtained either at Cape Armitage or Hut Point. It is difficult from the above Table 
to deduce any definite facts relative to the rate of growth, as, from the same locality 
and on precisely the same date, specimens were obtained with extreme total lengths 
of 66 mm. and 161 mm., a difference of 95 mm. The mean date of capture may be 
taken as March, and the mean length of the embryos included in the above Table 
(excluding Nos. 24 and 25, the dates of capture of which are not given) is 155 mm., 
or, including the tail, 127°5 mm. The average length of those obtained during 
February (9th to 25th) is 99 mm., while that of the thirteen taken in March 
(1st to 20th) is 149°6 mm. Taking the mean dates in these two months as 
February 17th and March 10th, we arrive approximately at a rate of growth of 
50 mm. in 21 days. Supposing this to represent the rate of growth from the 
commencement, it follows that the date of sexual pairing would be in the early part 
of January. From these figures one may also estimate the period of mating as being 
not less than six weeks. 
Major Barrett-Hamilton states (2) that the young of Weddell’s Seal are 
born on the ice in September. Dr. Wilson, in his appendix to Capt. Scott’s “ Voyage 
of the ‘ Discovery,” however,-says that they were able to observe the breeding habits 
and that the young were born “during the last week of October and the beginning 
of November.” ‘This difference of two months may possibly be accounted for by the 
difference in latitude. The young specimen (three months old) described by Major 
Barrett-Hamilton was found by the ‘ Belgica’ Expedition in 70° 18” 8. Lat., whereas 
those observed and collected by the ‘ Discovery’ were obtained about 78° 8. Lat. 
It may therefore safely be concluded that the period of gestation in the seals is 
not less than nine months, probably rather longer. Nine months is the time given 
by Sir William Turner, though he does not mention the data upon which he based 
the statement. 
It is evident that the rate of growth as estimated above for the earlier period 
of intra-uterine life must be increased during the later periods, otherwise a young 
animal born in the early part of November would measure but just over 600 mm., 
which is considerably exceeded in my oldest uterine specimen. The development of 
the hair, the descent of the testes, and other factors, lead to the conclusion that this 
largest foetus could not have been far from completing its uterine existence. 
DESCRIPTION OF THE EXTERNAL CHARACTERS. 
Colour.—With the exception of the two oldest specimens, all the embryos are 
destitute of hairy covering and are of an ivory-white colour, due no doubt in part to 
the action of the preservative fluid. The only pigment visible gives rise to a narrow 
black line along the margin of each eyelid, where it makes its appearance at a very 
early age. The two largest specimens showed considerable colouration ; in the younger 
BQ 
