1864.] IN THE MUSEUMS OF HOLLAND AND BELGIUM. 397 
high, with very short acromial and coracoid processes. The humerus 
15" long. The radius 163" long, and 10" broad at its distal end. 
The ulna 8" broad at}the same part. The thumb is absent; the 
digits differ but slightly from each other in length. The second, 
third, and fifth have, besides the metacarpal bones, each four pha- 
langes ; the fourth has five ; but, as they are artificially articulated, 
these numbers are not entirely to be depended on. 
Megaptera longimana.—A nearly complete skeleton of a young 
animal, obtained from Greenland through Eschricht. It is 28! 7" 
long, of which the skull is 7! 7". There are but thirteen ribs present. 
Genus Physalus.—A skull of a young specimen, agreeing in all 
its characters with P. antiquorum, Gray; marked “ Balenoptera 
physalus, Mer Sept.” Its length, from the condyles to the tip of 
the beak in a straight line, is 10! 6’. 
Genus Sibbaldius.—A skeleton marked “ Balenoptera physalus, 
Vinvisch, Zuider Zee.’ This is no. 17 of Eschricht’s list (Unter- 
suchungen tiber die Nordischen Wallthiere, Leipzig, 1849), accord- 
ing to which it was taken in the Zuider Zee, near Monnikendam, 
Aug. 29th, 1811, its length being 32' Rheinland. The skeleton is 
perfect, with the exception of the hyoid and pelvic bones. The 
malars, lachrymals, and tympanics are present. The entire length 
(including the skull, which is 6! 7!) is 29' 7"; but the bodies of the 
vertebree are placed close together, so that 2 or 3 feet should be 
added for the intervertebral spaces. The animal was young; the 
epiphyses of all the vertebrae, including that of the hinder surface 
of the axis, are separate from the bodies, as well as those of both 
ends of the humerus, radius, and ulna. The vertebral formula is 
C. 7, D. 13 or 14, L. 16 or 15, C.19=55; but the last caudal is 
elongated, and really consists of two bodies ankylosed, with even a 
minute rudimentary third. The cervical vertebre exhibit all the 
characters peculiar to the genus ; but their lateral processes are, as the 
surface of the bone shows, incomplete at the ends. The atlas has 
a deep, compressed-from-before-backwards, short transverse process, 
and a backward-directed, median triangular projection on the under 
surface of its body for articulation with the axis. The five following 
vertebree have each an upper and lower transverse process, but not 
united together at their ends in any of them—not quite, even in the 
second. The processes are of tolerably equal length throughout, 
except the lower one of the sixth vertebra, which is shorter and 
broad, and twisted on itself so that its flat surface is horizontal at 
the end. The upper processes are slenderer than the lower, and 
become more so posteriorly. The spaces between the upper and lower 
processes, in vertical height, are in the second 2!'-2, in the third 4!-2, 
in the fourth 4''-2, in the fifth 4/1, in the sixth 4!"7, The spines 
are comparatively well developed, especially that of the axis. 
There are thirteen pairs of ribs present; but it is probable that 
the posterior pair are wanting. The first has a bifid articular head, 
the cleft extending to the depth of 5 inches. It articulates by this 
with the transverse processes of the seventh cervical and first dorsal. 
Its extreme length in a straight line is 21"; its breadth at the middle 
