On the Laws of the Disti^ibution of Life and of Rocks. 405 



gulum ani distincte excavate, aliter directo ; veuis omnibus fere 

 velut in Tayyetide. Caput oculis nudis ; palpis eloagatis, extror- 

 sum paulum porrectis ; autennis tenuissimis, vix clavatis. 



Amphidecta piynerator, sp. nov. PI. IX. fig. 11. 



Alae supra fuscse, area apicali anticarum et margine apicali postica- 

 rum obscurioribus ; costa anticarum et angulo auali posticarum 

 roseo-rubris : anticse costa basali nigro liturata ; maculis tribus 

 discalibus albidis triangulum formantibus : corpus fuscum. 



Alae subtus pallidiores : anticse minime violaceo tinctae ; apice fusces- 

 cente; area apicali et costa nigro lituratis ; maculis velut supra, 

 quartaque intermedia cuneata submarginali, albidis, plaga pur- 

 pureo-fusca iuclusis : posticee albidee roseo tinctse, omnino fusco 

 striatae ; apice niveo ; angulo anali ferruginoso ; lineis duabus 

 mediis male definitis irregularibus ; margine externo fuscescente ; 

 punctis sex discalibus albis nigro punctatis, serie undata positis : 

 corpus ochreo-cinereum. 



Exp. alar. unc. 2-j^g. 



Hab. Ega. Coll. Bates. 



Taken in the depths of the forest. Flight low and weak. 

 Only a single specimen found. (Bates's MS.) 



XLIX. — The Method of Geology ; being an Account of the intro- 

 ductory part of a paper on " The Laws which have determined 

 the Distribution of Life and of Rocks," read before the Cam- 

 bridge Philosophical Society, Nov. 12^ 1866, By Harry G. 

 Seeley^ F.G.S., of the Woodwardian Museum in the Univer- 

 sity of Cambridge. 



In their disti-ibution over the world, the materials of rocks 

 which are accumulated under water, and the materials of 

 organized bodies, obey the laws of physics. The forces that 

 these laws relate to, in this subject, are: — in the first place, those 

 inherent in the earth itself, such as gravity and attraction, on 

 the one hand, and motion in the earth's crust ; and, secondly, 

 those acting on the earth from without, such as the heat received 

 from the sun, and attractive forces which determine the earth's 

 relations to the solar system. That is, everything is kept in its 

 place by gravity, out of which it is moved by heat and the forms 

 of energy into which heat is changed; while the area over which 

 these forces operate in a given way is changed by movements in 

 the earth's crust producing changes of land and water. 



2. The motion of matter visible on the land is for the most 

 part due to the sun's heat — hence being derived those distri- 

 buting powers the winds and rain and rivers, in their various 



Ann. ^' Mag. N. Hist. Ser. 3. Vol.xx. 28 



