Decembee 25, 1896.] 



SCIENCE. 



959 



crystals, thus showing that the substance be- 

 longed to the latter class. 



Action of Water of the Huhh Coal Mine upon 

 Cast Iron : By F. W. Durker. This mine was 

 flooded and was filled with water for several 

 years. When it was pumped out the iron work 

 was found to have undergone a considerable 

 change. The form was the same, but the sub- 

 stance was now porous, soft and easily cut with 

 a knife. The changes which had taken place 

 are explained as follows : the iron pyrites in 

 the coal had been converted into ferrous sul- 

 phate, sulphuric acid and sulphur. The acid 

 dissolved in the water and attacked the castings, 

 forming the sulphates of the metals, hydrogen 

 and hydrocarbons. The oxygen and carbon 

 dioxide dissolved in the water formed oxides of 

 iron, and the bars then consisted largely of 

 silicon with oxides of iron on the outside. 



The Action of Sulphuric Acid on Anisol: By 

 "W. B. Shober. Various results are found re- 

 corded concerning the action of sulphuric acid 

 on anisol. The author studied the reaction 

 tinder different conditions and found that 

 anisol disulphonic acid is formed in every case 

 in which anisol and sulphuric acid were heated 

 to 92°; but not if they were heated above 

 125°. Paranisolmonosulphonic acid was always 

 formed, while the ortho compound was formed 

 when the substances were brought together at 

 the ordinary temperature. This number also 

 contains reviews of the ' Journal of Physical 

 Chemistry;^ ^ Jahrbuch der Electrochemie ; '' 

 'Foods, their composition and analysis,' A. W. 

 Blyth ; 'The Elements of Electrochemistry,' 

 M. Le Blanc. J. Elliott Gilpin. 



SOCIETIES AND ACADEMIES. 



ZOOLOGICAL CLUB, UNIVERSITY OF CHICAGO. 



MEETING OF DECEMBER 2, 1896. 



The meeting opened with a papr by Dr. O. 

 P. Hay, on ' The Structure and Mode of Devel- 

 opment of the Vertebral Column,' of which the 

 following is an abstract: 



A vertebra is in most, if not all, animals a 

 composite structure, both in the early stages of 

 ossification and in the preceding cartilaginous 

 stage. The notochord, around which the verte- 

 bral centrum is developed, at a very early 

 period secretes two sheaths, an outer one, the 



elastica, and an inner thicker one, the proper 

 chordal sheath. Any segmentation of the noto- 

 chord or of its sheaths is due to the development 

 of structures lying primarily outside of the 

 sheaths and arranged metamerically. The 

 skeletogenous cells arise from the lower half of 

 the proto vertebra, Gadow and Abbott to the 

 contrary notwithstanding ; from these cells arise 

 the upper and lower arches and the intercalated 

 cartilages. In the sharks, cells from the bases 

 of the arches pierce the elastic and enter the 

 chordal sheath, thus giving rise to the centra 

 of these fishes. In the bony fishes, as Gegen- 

 baur and Balfour have shown in Lepidosteus, 

 Lotz in the salmon and Hay in Amia, the ele- 

 ments of the vertebral centra are developed 

 wholly outside of the elastica. In the tail of 

 Amia there are for each myomere eight carti- 

 lages resting on the elastica, the two halves of 

 the upper arch, the two halves of the lower 

 arch, the two upper intercalated cartilages, and 

 the two lower intercalated cartilages. In the 

 dorsal region these are all present except the 

 lower intercalated cartilages, which seem to be 

 missing. 



A deposit of bone is formed in each of the 

 eight pieces of each segment of the tail. The 

 four bases of the upper and lower arches are 

 thereby joined into one of the two rings found 

 there in each segment, the so-called hypocen- 

 trum or intercentrum ; similarly the four inter- 

 calated cartilages are joined to form the other 

 ring, the so-called pleurocentrum. In the dor- 

 sal region the bases of the upper arch take na 

 part in the formation of the centrum, being 

 crowded upward on the top of the enlarged in- 

 tercalated cartilages. Bone spreading from the 

 latter cartilages meets bone advancing from the 

 bases of the lower arch. Hence the vertebrae of 

 the dorsal region are called pleuro-hypocentra. 



In Lepidosteus the intercalated cartilages ap- 

 pear to be fused into a ring around the noto- 

 chord and thus fused with the bases of the up- 

 per and lower arches. Later this ring of inter- 

 calated cartilages is divided, one-half going to 

 the vertebra behind, the other half to the verte- 

 bra in front, and these, becoming ossified, form 

 the articular ends of the adult vertebra. 



In the Urodeles the two sheaths of the noto- 

 chord are enveloped as in bony fishes. Hasse 



