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POPULAR SCIENCE REVIEW. 
giving its abdomen an undulating movement, tbe spines serving as a support 
against tbe walls of tbe cell, tbe larva travels towards tbe operculum in tbe 
same way that an ear of rye, by means of its spiny beards, can travel over a 
piece of clotb wbicb is set in vibration.’ M. Brongniart says that tbe spines 
are not upon tbe abdomen itself, but upon tbe cerci, or caudal appendages, 
wbicb constitute two large mamillse. Tbe legs are also covered with spines 
wbicb assist tbe larva in its movements. Tbe larvae of tbe upper part of tbe 
case are tbe first to issue, although these eggs are the last laid. On escap- 
ing from the egg-case, tbe young larvae, instead of dropping to tbe ground, 
are suspended in tbe air by means of two long silken threads, attached by 
one end to tbe cerci already mentioned, and by tbe other to tbe inner wall 
of tbe egg-case. In this way, when all have emerged, they form a sort of 
bunch, and they remain thus for some days until their first moult tabes 
place, when they leave their cast skins suspended from the case. (Ann, 
Mac/. Nat. Hist., August, 1881.) 
Rhizopods, Food for Fishes . — Prof. Leidy reports that tbe young of some 
of the suckers (Catostomidae), such as Hypentelium , Myxostoma, &c., have 
been found by Mr. S. A. Forbes, of Illinois, to have tbe intestines packed 
with tests of Difflugia and Arcella , indicating that they fed on Rhizopods. 
In a slide containing material from tbe intestines of a young mullet (Myxo- 
stoma macrolepidotum ) from Mackinaw Creek, prepared by Mr. Forbes, 
Dr. Leidy distinguished Difflugia glohulosa and D. acuminata; and in 
another of tbe food of Fremyzon saccata, be found Difflugia glohulosa , 
D. lohostoma, D. pyriformis, Arcella vulgaris, and A. discoides , besides 
another peculiar undescribed form. (Amer. Jour. Sci., July, 1881.) 
Division of Fnglypha alveolata. — Prof. Gruber has described (Zeitschr. 
fur wiss. Zool., Bd. XXXV. p. 431) an exceedingly interesting process of 
division observed by him in tbe fresh-water Bhizopod, Fnglypha alveolata. 
Tbe test of this elegant creature consists of little circular concavo-convex 
discs, covering tbe superficial layer of tbe sarcode-body. Similar little discs 
also exist in tbe interior of tbe body in tbe neighbourhood of tbe nucleus. 
"When tbe sarcode-body begins to grow out of proportion to tbe test, a por- 
tion of tbe contents of tbe latter protrudes from its orifice, and gradually 
increases in bulk, and into it pass by degrees tbe little discs contained in tbe 
interior of the body, and group themselves into a structure resembling a fir- 
cone, wbicb clothes the surface of tbe protoplasmic process. By tbe con- 
tinued increase of tbe latter tbe little discs are pushed further and further 
apart, until this part acquires exactly tbe form of the original animal, of 
wbicb there are then two, adhering together, with tbe orifices of their tests 
turned towards one another. It is only now that alterations commence in 
tbe nucleus, wbicb still retains its original position. First of all, fine granules 
and twisted lines make their appearance in it ; then it becomes extended in 
tbe direction of tbe long axis of the animal, whilst at tbe same time a dis- 
tinct longitudinal striation becomes perceptible, in consequence of wbicb tbe 
nucleus divides into two nearly equal parts ; of these one passes over into 
tbe process, where, like the half remaining into tbe original position, it soon 
resumes a pale, nearly vesicular appearance. Now' by a rapid circular 
flowing in tbe sarcode, a mixture of it takes place, tbe body draws back 
here and there a little from tbe test, and finally tbe two halves separate as two 
