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POPULAR SCIENCE REVIEW. 
found to pour their secretion into the cavity of the mouth, and not into the 
nippers. Mr. M'Leod, during a residence in Java, took the opportunity of 
examining some of the large centipedes with which that island abounds, 
and especially Scolopendra horrida ; and finding that, as above stated, the 
glands which might easily be taken for poison glands had nothing to do with 
the nippers, which, nevertheless, always exhibited a very distinct orifice at 
the tip, he was led to search for the glands in the interior of those organs 
themselves. 
The process he adopted is one that has of late given admirable results in 
the investigation of the anatomy of many animals ; namely, the preparation 
of sections of them in various directions after they had been immersed in 
melted paraffin, the subsequent hardening of which keeps all parts in their 
natural positions during the operation of cutting. By this means he detected 
the poison gland, which is situated partly in the actual biting portion of the 
nipper, and partly in the broad basal joint which supports the latter. The 
glandular apparatus consists of a chitinous duct leading to the orifice at the 
apex of the organ, and forming the axis of the gland. It is perforated in its 
course by a multitude of small apertures, each of which leads into a minute 
cylindrical tube terminating in a long secreting cell, the whole mass of these 
cells being arranged in a radiating fashion around the duct. The entire 
organ is surrounded by a membrane, and has the general form of a four-sided 
prism. Notwithstanding its comparatively small size, Mr. McLeod has 
detected the same arrangement in Lithobius forficatus (the common Euro- 
pean centipede). — Bull. Acad. Roy. de Belgique , tome xlv. 1878. 
Sponge-borings in Marble. — Most naturalists are aware of the power pos- 
sessed by certain sponges forming the genus Cliona of boring into the shells 
of mollusca and other hard bodies, but we are hardly prepared to hear of 
their making their way into so refractory a substance as statuary marble. 
Prof. Verrill, however, states (Sillimaris Journal , November, 1878) that the 
Peabody Museum of Yale College has lately received some fragments of 
white Italian marble from a cargo wrecked off Long Island in 1871, and 
taken up this year, in which “the exposed portions of the slabs are thoroughly 
penetrated to the depth of one or two inches by the crooked and irregular 
borings or galleries of the sponge Cliona sulphur ea, V.,” and reduced “ to a 
complete honeycomb readily crumbling in the fingers. Beyond the borings 
the marble is perfectly sound and unaltered.” Prof. Verrill remarks that 
the possession of such boring powers by this apparently insignificant sponge 
may have a practical bearing in the case of submarine constructions of lime- 
stone or similar materials. 
