I78 JOURNAL OF CONCHOLOGY, VOL. 9, NO. 6, APRIL, 1899. 



Calcium butyrate is less soluble in hot than in cold water. In the 

 case of a specimen of Strombus tricornis, a small piece of greyish 

 gelatinous matter came from the interior of the shell. This was 

 proved to be organic matter by the two following tests : — 



4. — A portion was heated to redness in a porcelain basin. It 



charred, giving off the odour of burnt feathers. 

 5. — Another portion was heated in a hard glass tube, with a small 

 piece of sodium. The tube, whilst still hot, was plunged into 

 cold distilled water, and the whole filtered. 

 The filtrate was tested 



(a) With sodium nitroJ>russide, which gave a purple colora- 

 tion (sulphide). 



(b) With ferrous sulphate and ferric chloride ; on adding 

 dilute hydrochloric acid, a blue coloration was produced, 

 shewing the presence of a cyanide, derived from the nitro- 

 genous matter of the piece of substance examined. 



The solution obtained by the maceration of the shells was filtered, 

 and the clear filtrate tested as follows : — 



6. — A few drops of acetic acid and then ammonium oxalate solu- 

 tion were added. A heavy white precipitate showed the 

 presence of much soluble calcium salt. 

 7. — Dilute nitric acid and silver nitrate solution were added. 



No precipitate showed the absence of a chloride (salt, etc.). 

 8. — Dilute nitric acid and barium nitrate solution were added. 

 No precipitate was formed, showing the absence of a sulphate. 

 9. — Neutral solution of ferric chloride was added. A deep red 

 coloration was produced, and on boiling a reddish-yellow 

 precipitate was thrown down, showing the presence of an 

 acetate. 

 10. — A few drops of alcohol and strong sulphuric acid were added, 

 and the whole was warmed thoroughly. A pleasant odour 

 was evolved, resembling that of pears. This pointed to the 

 presence of butyric acid. In order to confirm this, a little 

 pure butyric acid was neutralised with caustic soda and 

 warmed with alcohol and sulphuric acid. An identical odour 

 was evolved. There can be no doubt that the white powdery 

 substance is calcium butyrate. 

 My best thanks are due to Mr. W. H. Hurtley, B.Sc, for his help 

 in conducting these experiments, and to Mr. R. Standen for many 

 kind suggestions. 



I shall always be pleased to receive criticisms or suggestions. 



8, Sea View Terrace, 

 Seaton, Devon. 



