MADEIRAN COLEOPTERA. 191 
nearly glabrous, and, when viewed beneath the microscope, ap- 
pearing closely and coarsely transversely-strigulose,—the lines 
being much waved; the former large, and subquadrate-ovate ; the 
latter with a longitudinal series of six punctures down either side 
of its disk, and with a few scattered ones between them and the 
edges. Elytra considerably diluted in colouring, being brassy- 
piceous (sometimes almost brassy-testaceous), pubescent, and 
deeply and rugosely punctured. Antenne at base, and the legs, 
testaceous ; but unequally infuscated in parts. 
Four specimens of the present Philonthus (which is stated by 
Kraatz to be allied to the European P. eaiguus) were mixed up with 
my series of the P. aterrimus formerly taken in these islands ; and it 
was not until the summer of 1855 that I perceived my mistake in 
confounding a second species under (what I had regarded as) the 
latter. As it will be inferred therefore, the P. semulans very much 
resembles, at first sight, the aterrimus ; nevertheless it is abundantly 
distinct therefrom, in reality,—not merely in its external features, 
but likewise in its habits. As regards the former, its slightly larger 
size (on the average) and more developed head, in conjunction with 
its brassy surface, its more diluted and deeply punctured elytra, and 
the transversely-strigulose sculpture of its head and prothorax, which 
is exceedingly apparent when viewed beneath the microscope (and 
which is scarcely at all traceable in the aterrimus), will readily cha- 
racterize it ; whilst, as regards the latter, it is an insect of a some- 
what higher range than its ally, attaining its maximum within the 
dense forest-districts of intermediate and rather lofty elevations. 
Moreover, whilst the P. aterrimus is more particularly abundant at 
the edges of the water-courses and streams, the simulans occurs 
especially beneath decaying leaves; and has also the curious habit 
of counterfeiting death, when captured, by bending its head against 
its prosternum, and partially curving its abdomen downwards, after 
the fashion of a Xantholinus,—a peculiarity which I have never ob- 
served in the P. aterrimus, nor indeed (so far as I can recollect) in 
any member of the present genus. 

543. Philonthus nigritulus. 
Staphylinus nigritulus et aterrimus, Grav., Col. Micropt. 41 (1802). 
Philonthus aterrimus, Erich., Gen. et Spec. Staph. 492 (1839). 
, Woll., Ins. Mad. 584 (1854). 
—— nigritulus, Kraatz, Nat. der Ins. Deutsch, ii. 616 (1857). 
Inhabits Madeira and Porto Santo; abounding at the edges of the 
streams, and in other damp spots, at low and intermediate elevations. 
Dr. Kraatz having recently assigned a sufficient reason for accepting 
the name of nigritulus for this insect, instead of aterrimus (the date 


