358 Linncean Society. 



scalpel ; but it has a membranous and closer connection, and towards 

 its base it is more intimately attached by muscular fibres proceeding 

 from the elevator muscles beneath, which are lost in the fascia cover- 

 ing its sacral surface. 



" The quills of the upper tail -covert are inserted obliquely into this 

 triangular mass of cellular substance, each quill having its peculiar 

 capsule, which seems to be formed of condensed cellular membrane : 

 between each quill there are small muscles, the fibres of which run 

 in parallel lines extending from one quill to the other ; and besides 

 these muscles there are other small ones, the fibres of which run ob- 

 liquely in such a direction as somewhat to resemble the letter V; the 

 interstices of these muscles are filled with cellular substance. 



" By the powerful action of the sacro-coccygeal and the sacro-su- 

 pracaudal muscles, the true tail is elevated, and at the same time the 

 upper tail-covert is raised perpendicularly and supported by the pro- 

 per tail, and perhaps the swelling of these muscles in their contrac- 

 tion exerts some influence in spreading the feathers of the upper tail- 

 covert. The principal agents in this office are the small muscles 

 situated between each quill, by the contraction of which the quills 

 are brought closer together, and consequently the opposite ends of 

 the feathers are proportionately separated from each other. The 

 small muscles of which the fibres diverge have not only the power of 

 contributing, by their contraction, to the spreading of the feathers 

 of the upper tail-covert, but they exert considerable influence in 

 raising the feathers perpendicularly. There can be no doubt also, 

 that the slips of muscular fibres coming from the sacro-coccygeal and 

 sacro-supracaudal muscles exert their influence in the same office. 



" Although these small muscles are very powerful, they would be 

 quite inadequate, alone, to the office of raising perpendicularly, 

 spreading the feathers and maintaining them for any considerable 

 time, were it not that the feathers of the upper tail- covert are partly 

 raised and maintained in this position by the elevation of the true 

 tail." 



The paper was accompanied by coloured drawings, representing 

 in detail the muscular apparatus in the tail of the Peacock. 



Read also a memoir " On the Solid Vegetable Oils." By Edward 

 Solly, Jun., Esq,, F.R.S., F.L.S. &c. 



Mr. Solly commences his paper by referring to the usual division 

 of oils into three classes, the fat, the drying and the volatile. The 

 fat oils vary in their properties according to the relative propor- 

 tions which they contain of Elaine or fluid oil and of Stearine or 

 solid oil ; those which contain much of the former being fluid at 

 ordinary temperatures, while those which contain a larger quantity 

 of stearine are solid under ordinary circumstances and constitute 

 the class of Tallows or Butters. Of these the vegetable kingdom 

 affords a very considerable number ; and Mr. Solly having recently 

 received specimens of several, has collected in the present paper a 

 large amount of information concerning them, to which he has added 

 his own observations. He arranges the Vegetable Butters or Tallows 



