216 PERCY SLADEN TRUST EXPEDITION 
Rather shortly and broadly oval, shining pitchy-black above, the base of the thorax 
sometimes narrowly testaceous and the suture of the elytra sometimes vaguely ferruginous; 
under-side dark pitchy ferruginous ; palps and antennee yellow, clubs of the latter blackish. 
Submentum bearing a transverse series of long hairs (absent in B. silhouette), standing in 
a shehtly curved line. Head with very fine scanty punctuation near the anterior margin ; 
rest of head and prothorax quite smooth and impunctate (only under a compound micro- 
scope is an extremely scanty and obsolete punctuation visible). Scutellumsmooth. Llytra 
with the outer margins slightly flattened towards the apex, rather strongly and regularly 
punctured, the punctures arranged in a number of closely-approximated series ; in each 
series the punctures are well spaced out, at some distance from one another, and those in 
each alternate series are slightly stronger. The seriate nature of the punctuation is not 
always quite evident at first sight, but is very clearly visible if an elytron is removed and 
examined separately. Certain peculiarities of the sterna are mentioned in the description 
of the genus (see Pl. 14, fig. 20). 
Antenne (Pl. 14, fig. 13): in the ¢ the antenna consists of only eight joints, as 
opposed to nine in the ¢; it has only two short transverse joints between the slender 
elongated third jot and the club, instead of three as in the 2. When balsam- 
preparations of the g¢ antenna are viewed as transparencies under a high power 
(4-inch objective), there is an indication that the proximal of these three transverse 
joints, z.e. that which corresponds to the 4th joint in the ?, may have fused with the 
third joint, thereby reducing the number in the $ from 9 to 8. Usually the number of 
joints cannot be surely determined without making balsam-preparations, and there is 
no other external sexual differentiation: but when several transparent balsam-mounts 
were made, the sexes were easily distinguished by the genital structures within the apex 
of the abdomen, and it was then seen in each case that the ? antenna has 8 joints, 
the 2 9. 
The series consists of about 100 specimens. 
Loc. Seychelles. Mahé: summit of Morne Pilot, over 2000 feet, X.—XI. 1908; 
high forest between Trois Fréres and Morne Seychellois, about 2000 feet, 9 and 10. 
XII. 1908; slopes of Morne Seychellois, about 2000 feet, 4. II. 1909; high forest above 
Cascade Estate, I. 1909; summit of “ Montagne Anse Major” (Mare aux Cochons district), 
about 2000 feet, 1. IT. 1909. 
18. Bourdonnaisia silhouette, sp. nov. (Plate 14, figs. 16 and 21). 
22. Major, magis elongata, elytris parum subtilius punctatis; mesosterno et meta- 
=) Sate, Cry Cesar 
sterno in medio argute longitudinaliter carinatis. Long. corp. ca. 24 mm. 
¢ et 2, antennis 9-articulatis. 
Much larger ; form more elongate-oval as contrasted with the short broadly-oval form 
of B. mahensis. Elytra with the margins a trifle less explanate behind, and with the 
punctuation slightly finer. Maxillary palpi darker in colour. Thorax sometimes testaceous 
on either side at the base. Peculiarities in the form of the sterna (see Pl. 14, fig. 21), as 
compared with that of B. mahensis, are mentioned in the description of the genus. 
