174 ZOOLOGY. 
thorax, the expiration of air through the proboscis, special organs 
attached to the abdomen, vibrations of the thoracic rings, and 
vibrations of the wings in rapid motion. A very complete and 
ingenious series of experiments conducted by Mr. Mosely seem 
to place beyond doubt the conclusion that the sound is produced 
by the proboscis, the note being formed at a narrow slit-like open- 
ing at the base of the trunk, and being modified by passage through 
the proboscis, and by vibrations therein set up.— A. W. B 
MODE or JNcREASE OF THE Loxe Bones.— A paper on this sub- 
ject appears in the last part of the Archives de Physiologie, by 
MM. Philippeaux and Vulpian. The views generally adopted in 
regard to the mode of growth of the long bones, both in length 
and diameter, have been called in question by Wolff and Volkmann 
in papers recently published ; and MM. Philippeaux and Vulpian’s 
researches were undertaken with the object of ascertaining whether 
their objections are well founded. The doctrine supported by the 
authority of Duhamel, Hunter, and Flourens, and generally ac- 
cepted, is that the long bones increase in length by additions to 
the extremities in the form of new layers between the shaft or 
diaphysis and the articular portion or epiphysis, while they become 
_ broader by the deposition of new bone in the periosteum on the 
outer surface of the bone. M. Wolff, on the other hand, maintains 
that the growth of bone is interstitial, and that each part of the 
bone takes part in the enlargement. He points to the persistence, 
during growth, of the position and relations of the peculiar and 
geometrically arranged trabecule of the cancellous texture consti- 
tuting the head of the bone, which could hardly occur on Duhamel’s 
theory. He denies Duhamel’s statement that a ring surrounding 
the bone of a young animal comes by degrees to occupy the shaft 
_of the bone, owing to absorption of the old bone and the superpo- 
sition of new; but contends that the old bone is pressed inwards, 
and is certainly not absorbed. He further states that when wires 
are passed through both the epiphysis and two points of the diaphy- 
sis, the distance between the two latter augments just as much as 
the distance between the wire passing through the epiphysis and 
that through the diaphysis lying nearest to it. MM. Philippeaux 
and Vulpian oppdse M. Wollff’s statements. They state that rings 
„encircling the bone, as well as metallic lamellæ, interposed between 
their "r! u p er are z fres, or almost free, in the medaliary 
; periosteum and osseous tissue in young “animals, do actually 
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