380 [August, 



pure sulphate with seven equivalents of water crystallized right rhombic, and 

 had ttie form, appearance, taste, and gave all the reactions of epsom salt. It 

 gave me 50.8 per cent, of water, and 30.5 per cent, of sulphuric acid, which also 

 prove that I had sulphate of magnesia. The analysis of the mineral is, accord- 

 ins to J. L. Smith: 



According to these analyses the mineral is Saponite. 



As the original communication appeared in your Journal, I think it proper to 

 forward the above." 



Mr. Grirard exhibited colored drawings of two species of the genus 

 Sdlino, referring one to S. eri/divoy aster ^ De Kay, and the other he con- 

 siders as undescribed. 



*' Its large scales and fusiform body would undoubtedly recall to mind the 

 salmon, but on a more close examination the general shape and outline 

 are far more elegant than in the salmon, preserving altogether better pro- 

 portions between the different rei:ions of the body. The head forms about 

 a fourth of the entire length, whilst in the salmon it is about the sixth only. 

 I'he eyes are of medium size, and subcircular in shape, their diameter being co. - 

 tained nbout seven times in the length of the head. The posterior half of the 

 max.llary which is regularly and most decidedly curved downwards, gives to 

 the shape of the mouth quite a peculiar aspect. The anterior margin of the dor- 

 sal fin is equidistant between the tip of the snout and the base of the caudal. 'J he 

 posterior margin of the latter is regularly crescent-shaped. The adipose is 

 elongated, club-shaped, and situated opposite the posterior half of the anal. The 

 ventrals are inserted under the middle of the dorsal, somewhat nearer the anal 

 than the pectorals. The scales are remarkably large, contrasting greatly when 

 compared to those of S. eiytJirogaster, S. fojiti7ialis^ and S. Jiamayci/sh., o\ amethys- 

 tits. There are about a hundred and fifteen of them in the lateral line. 



The color in the female is uniform silvery grey, darker on the hack and head. 

 Subquadrangular or subcircular black spots are observed upon the sides of the 

 head, behind the eyes, along the brick, and the half of the flanks, aUo on the dor- 

 sal and caudal fins, to nearly their ed>;e. In the male these same colors e>;i>t, 

 but spread all over with a reddish tint, more intense on the flanks and benei^th 

 than upon the head, back, and dorsal and caudal fins, where the red is sometin;es 

 but faintly indicated. The name of Sa/mo selapa is proposed for this species, 

 which inuabits the southern part of the State ol Maine. 



Mr. Girard, referring to a communication made to the Academy some 

 weeks since by Prof. Agassiz, on the sui)jcct of (crawfishes, remarked : 



Previous to the publication of his " Revision of the North American Astaci," 

 &c.,he was well acquainted with the fact that the ^qv\w% Astacvs jn-ojier, as now 

 understood by Prof. A., was represented in North America. He further knew 

 that this fact was demonstrated by Prof. J. 1). Darin, in a paper published pp. 

 10 28, of vol. vi. (Jan. 1852), of the Proceedings of the Academy, and that con- 

 sequently Prof. Agassiz had no claim upon that discovery. 



As to the circumstance that Camharus Gamhelii may be referred \o Antaeus on 

 the ground of having eighteen branchiae instead of seventeen, Mr. G. said he was 



* The sesquioxide of iron and alumina contain a trace of Silica, which was not 

 separated. 



