THE 
AMERICAN NATURALIST. 
Vo.. xv. — WAY, 1881. — No. 5. 
THE ENDOCRANIUM AND MAXILLARY SUSPEN- 
SORIUM OF THE BEE}! 
BY PROF. GEORGE MACLOSKIE, LL.D. 
i Soha chitinous wall which covers an insect’s body and lines its 
interior, is soft and thin for hinges and other pliable parts, and 
is hardened in places where rigidity is required. It is further- 
more folded outwards or inwards into processes which impart 
additional strength or protection, or for attachment of muscles. 
The outgoing folds are seen in the pleura of a lobster 
(allied to insects) and the wing of a bee, and are always double 
by nature (including the outgoing and returning plates) with 
interposed nutritive matter, like the meat in a sandwich. 
The outgoing plates (or exodemes) have their counterparts in 
the internal processes (or endodemes), which usually mark the 
boundaries between adjacent segments of the body, and which are 
more or less hardened in particular parts, thus forming an endo- 
Skeleton. This internal skeleton is most completely developed in 
the ventral part of the thorax, and where it forms the endocran- 
‘um, or internal buttresses of the skull. (It may be observed 
that the insect has also hard processes of the pharynx and 
Stomach which may be collectively termed its splachnodemes.) 
Anatomists have not paid much attention to this class of struc- 
tures, and some eminent students of insect embryology are as 
Silent regarding the endoskeleton as if they had never heard of 
Paper read before the Biological Section of the American Association for the 
Advancement of Science, Boston, Aug., 1880 
VOL, Xv.—No, v, 25 
