INSECTA MADERENSIA. 69 



out tlie entire sylvan regions, and occasionally indeed extending even a little 

 beyond them. It is the prevailing species in the upland district of the Fanal, 

 and on most of the alpine Serras where the forest, although on a gigantic scale, is 

 less dense, and is gradually becoming extinct. Xevertheless, though attaining its 

 maximum in these elevated tracts, it is by no means peculiar to them, since it 

 exists, more or less abundantly, at all altitudes between the limits of from 2500 to 

 5000 feet above the sea ; and at all seasons of the year. I have taken it in great 

 profusion, in July, at the Lombo dos Pecegueiros, the Cruzinhas, and the Fanal ; 

 as also, more sparingly, at the head of the Ril^eiro de JoRo Delgada ; at the Feijaa 

 de C6rte, in August ; and at the E-ibeiro Frio diu'ing the mnter and early spring. 

 I possess an example from the south of the island (I believe from the Cui'ral das 

 Romeiras) which is somewhat larger and more convex than the ordinary type, and 

 has its prothorax proportionably a Kttle smaller and more quackate ; bvit I con- 

 ceive it to be merely a local state of our present insect, and without even the claim 

 to be regarded as a permanent variety. 



53. Trechus alticola, WoU. 

 T. oblongo-ovatus subconvexus nigro-piceus politissinms, prothorace subquadrato basi vix angustato 



et utrinque impresso angulis posticis obtusis, elytris leviter striatis, antennis pedibusque pallidis, 



tibiis distincte infuscatis. 

 Long. Corp. lin. 2. 



Habitat sub lapidibus in montibus superioribus Maderse; — supra fastigium saxosura in ascensu 

 mentis Pico dos Arieros dicti, Meya Metade prospiciens, tempore hiberno et vernali a.d. 1849 a 

 meipso captus. 



T. oblong-ovate, a little convex, exceedingly shining, and piceous-black. Prothorax subquadrate, not 

 quite so much narrowed behind as that of the T. ciistos ; the posterior angles obtuse but scarcely 

 at all rounded; with a dorsal channel; and a distinct fovea on either side at the base. Elytrii 

 ovate, very lightly striated ; aud with two distinctly impressed points on the disk of each near 

 the third stria from the suture, which is somewhat more perceptibly pale than in the last species, 

 especially behind. Antenna and legs as in the T. custos, only with the tibiee, particularly towards 

 their apex, more evidently infuscate. 



This is the only Madeu'an Trechus of which I have the slightest doubt as to the 

 true specific claims, since it unquestionably approaches the T. custos very closely : 

 nevertheless since the minute points wliich separate it from that insect appear to 

 remain constant, and since in its habits it recedes from the rest of the genus here 

 described, I have thought it better not to unite the two, until at all events further 

 evidence shall decide the question. It is the only one, so far as I am aware, in 

 Madeu'a proper, the normal range of which would seem to be extra-sylvan, the 

 single locality in which I have hitherto observed it being the lofty uplands be- 

 tween the Ice House Peak and the Pico dos Arieros, — at an elevation of not less 



