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helonging to Hydroid Acalephs, the Tabulata. The Tabulata are 

 known to be Hydroids by direct observation of the animal in 

 Millepora recently made by Prof. A. in Florida. Of Rugosa no 

 living types are known, and consequently its affinities must be 

 determined by the structure of the solid parts. In this respect 

 the Tabulata present striking differences from the genuine corals 

 formed by the Polyps. These have vertical radiating partitions, 

 extending from top to bottom, with transverse partitions extend- 

 ing only between two adjoining vertical partitions. In Rugosa 

 this horizontal floor extends across the whole cavity of the animal, 

 as in Tabulata ; and the radiating partitions are limited in their 

 vertical extent to the space between two horizontal floors. So 

 that their affinities go with the Tabulata, in some of which there 

 are traces of radiating partitions. Besides, in Rugosa, the quad- 

 ripartite arrangement prevails as in Acalephs. The secretions 

 of the Tabulata are foot secretions, whilst those of other corals 

 are from the outer walls. 



Mr. John Green gave the results of an analysis of the 

 Scales of the Striped Bass, {Labrax lineatus) as follows, 

 viz : — 



In scales dried at 212° F., 45.9 per cent, of ash. 100 parts of 

 ash contained of Lime, 48.36 ; of Magnesia, .99 ; of Phosphoric 

 Acid, 50.65. This result is identical with the composition of 

 bone ash. The structure of bone is different in the Ganoid 

 fishes from that of any Cycloid or Ctenoid, and confirms the dif- 

 ferences already established from the appearances of the scales. 

 The scales of the Amia of the western waters, contain bone cor- 

 puscles of the same form and appearance as those of Megalops 

 and Lepidosteus, showing a new analogy of Amia with Ganoid 

 fishes. 



Mr. Theodore Lyman, referring to a large fragment of 

 Madrepore Coral, taken from the wreck of a British man- 

 of-war, and which he had exhibited at a recent meeting, 

 said, that he had since ascertained that the vessel was 

 lost about the year 1806, or half a century since. The 

 incrustation of the coral around the iron bolt shows that 

 the diameter of the coral must have been about three 



