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POPULAR SCIENCE REVIEW. 
direction from tlie base of tbe second pair of legs ; but instead of meeting, 
as in tbe first pair in tbe median line, are united by a transverse ridge, and 
a similar ridge is continued backwards from tbe points where this line joins 
those from tbe limbs. This arrangement reminds one of tbe bead of tbe 
larva of hexapod insect. No trace of palpi, mandibles, or suckers were 
found. Short jointed legs were found in all the specimens examined. 
From the above description it will be seen that this acarus agrees with 
sarcoptes for having a considerable interval between tbe second and third 
pairs of legs, and tbe absence of a furrow between them. 
Hearing the Tcenia echinococcus . — We believe tbe Taenia echinococcus has 
not hitherto been successfully reared in this country as a matter of experi- 
ment. It is therefore satisfactory to learn from a paper presented to the 
Royal Society by Mr. Edward Nettleship, that this gentlemen has culti- 
vated the echinococcus in the common dog. The following is a brief state- 
ment of the experiment On March 28, 1866, the liver and lungs of a 
sheep were obtained from Clare Market ; they contained numerous echino- 
coccus hydatids ; in some the outer cyst was partly calcified, but all the 
hydatids contained clear fluid, and great numbers of scoloces attached to 
the endocyst within two hours of the death of the sheep to which the organs 
belonged. Two or three of the smaller hydatids were given to a young 
dog about six months old — the hydatid being previously punctured — and 
the collapsed cyst administered. The dog was then made to drink the 
fluid of the cyst in which some echinococci were floating. On May 15 (the 
forty-seventh day after the first feeding), the animal was killed, and his in- 
testines were examined. In the first ten inches of bowel below the pylorus 
there were no taeniae y at that distance a single taenia echinococcus ap- 
peared, moving actively ; for the next two or three inches there were none, 
but at fourteen inches below the pylorus several more appeared, and im- 
mediately after this they became so numerous as to present almost the 
appearance of distended lacteals : this continued for about a foot in extent, 
and then they gradually became less numerous, and ceased at about three 
feet from the pyloric orifice. 
The Secreting Organs of Hemiptera. — Mr. Blanchard presented, accom- 
panied by an analysis, a memoir of M. Jules Kiinkel, upon the organs of 
secretion of the Hemiptera. The author has, in the first place, thoroughly 
studied the salivary glands of these insects, a subject on which our know- 
ledge is still very imperfect. He then extended his investigations to the 
organs which produce the sickening odour of bugs. The gland which ex- 
hales this odorous matter is, as we are aware, situated on the ventral or 
thoracic front of these animals, at the level of the two anterior legs ; but 
the nymphse and the larva are endowed with the same odour, though they 
do not possess the secreting gland. M. Kiinkel has discovered that this 
organ is replaced in the larvae by two dorsal pouches. When the insect 
undergoes its last metarmophosis, these two pouches become atrophied, 
while the ventral pouch, which is completely independent of it, becomes 
developed. It is easy to comprehend the purpose of nature in this substi- 
tution. The larva not having any wings, makes very good use of the two 
pouches which are on its back, in the most favourable situation, for driving 
away its enemies ; but if these two pouches existed in the same situation on 
