MR. W. H. FLOWER ON THE OSTEOLOGY OF THE SPERM-WHALE. 351 
obviously incomplete; the former has only eleven, and the latter ten. ‘Those that are 
present differ very notably in form and dimensions both from each other, and from 
those of the Tasmanian skeleton; but this is the most unsatisfactory part of the whole 
examination, owing to the imperfection of the materials and the difficulty, in incomplete 
sets, of ascertaining with precision which are the corresponding bones. 
Ribs. 
The ribs, though tolerably long, are (with the exception of the first) slender and light 
for the size of the animal, at least when compared with those of a Balena of correspond- 
ing magnitude. This character is best illustrated by stating that in the skeleton of the 
nearly adult Balena mysticetus, in the Mus. of Roy. Coll. of Surgeons, 46’ in length, 
the twelve pairs of ribs weighed 7 cwt. 60 lbs.; in the Cachalot, several feet longer 
and of corresponding age, the eleven pairs weigh less than 5cwt. Nevertheless their 
tissue is dense and compact. j 
It is stated by Wall that the ribs of the left side are of larger dimensions than the 
corresponding ones of the right. In order to ascertain whether there is a similar want 
of symmetry in the specimen under consideration, I weighed all the ribs; and the 
result shows considerable individual differences in corresponding ribs, and a very trifling 
general preponderance of the left side over the right—the total weight of the ribs of 
the right side being 165 Ibs. 93 oz., and those of the left side 164 Ibs. 53 oz. 
Weight and Measurements of the Ribs (excluding the rudimentary eleventh pair). 
7 
\Circumference | 
Extreme 1s 
Weight. length in eee i ce) at inferior | Curve *, 
straight line. : extremity. 
lbs. 02. in. in. in. in. 
ff Rear remt Pare hey Ie 27 6 45 14 29 103 
Main tetas euatay trevevaveri {oss c 27 ~=«4 47 | 14 28 11 
att senate oais etter hatin < 25 13 634 113 203 22 
1 in eee ee 25 1 63 113 20 21 
3 Re Re re aoe: 25 0 70 PB 173 28 
{i PEO CARS OO Cor 25 13 71s 94 18 27 
ie age ce me 21 8 71 92 16 29 
11. TIA Pores eas Det 7. BY 163 | "29 
5 go paradocs 2 19) 18, 68 8 14 30 
ce ee 21 7 72 83 15 | 29 
6 PUREE RY se wa 19195 673 9 123 29 
Iino t ostoe Domo aeee Oa 683 8? 12 28 
rp hl da es ninds caenciescieeeterS ia 654 8? 10 26 
dg |SleMectoge eetBeee... 16 15 663 83 103 25 
8 1A See Gee 15 3 63 83 8 22 
Lave ee es aires 13 15 65 8 84 224 
ph Blin, sag ho- ae. 3800 10:6 61 7 7A 19 
| Te eae ee, 10 5 63 63 gi 18 
if ie (AMIGA wT 9 72 56 7 83 | 11 
iat phases bates corey osif fava. s 8 43 557 63 8 113 
* Taken by standing the rib with its two ends on the floor, and measuring from the latter to the interior of 
the highest part of the arch. 
302 
