632 H. E. ANDREWES 



13. Vat*iopalpus crusoei Reed Proc. Zool. Soc. Lond. 1874, pp. 50 

 and 69. 



Masatierra, 6 ex., found under stones, 5. IV. 191 7. Confined to this 

 island. 



The specimens described by Reed were also found under stones at 1000 

 feet above sea level. 



Descriptions of new forms. 



Trechisibus fenioralis Germain var. backstrorni var. nov. 



Examples taken on Masafuera differ in some respects from the typical 

 form, but as they agree with it in most of their characters, and as the species 

 shows considerable variability, I treat it as a variety. The four specimens 

 before me vary somewhat in colour among themselves, and in one example 

 not only is the ferruginous colour on the elytra almost absent, except in the 

 marginal channel, but the striae are very lightly impressed. 



Head with flatter eyes, and with the part of the frontal foveae curving 

 round on each side behind them much less impressed. Prothorax narrower, 

 with the hind angles blunter and hardly projecting laterally, the reflexed lateral 

 margins not more than half as wide. Elytra with deeper striae, and, as in the 

 case of the prothorax, a much more widely reflexed lateral border. The 

 microsculpture is similar, that is to say with meshes averaging twice as wide 

 as long on the elytra, isodiametric on the head and prothorax. 



Masafuera, 4 ex., found under stones at 1300 metres above sea level, 

 27. II. 1917, 



On one of the cards two specimens were mounted, one of which, the 

 fifth example of the Masafuera series, was upside down, and, on being dismounted, 

 proved to belong to the typical form. As there were blanks elsewhere in the 

 Masatierra series, showing gum but no insect, I think it probable that this 

 specimen became detached and by inadvertence was remounted on a card with 

 the Masafuera label. 



Trachysarus sericeus sp. n. — Fig. i. 



Length: 7 — 8,5 mm. Width: 2,2-2,6 mm. 



Piceous black, elytra sericeous; palpi, antennae, borders of prothorax and 

 elytra, apex of elytra, pro- and epipleura, apex of venter, and legs more or 

 less ferruginous. 



Head massive, convex, smooth, and shiny, frontal foveae uneven, in the 

 form of an inverted W, the outer lines deep, running to the margins of eyes, 

 the inner ones shallower, meeting on middle of front, eyes flat, antennae some- 

 what dilated at apex, extending well beyond base of prothorax, tooth of 

 mentum obtuse and a little rounded. Prothorax rather flat, barely wider than 

 head, about a sixth wider than long, base a little narrower than apex, sides 

 very narrowly bordered, gently rounded in front and equally faintly sinuate 

 behind, a seta at a fifth from apex, hind angles slightly obtuse and rounded; 

 transverse impressions distant from margins, front one wide and deep, hind 



