224 Mr. T. Vernon Wollaston on 
it for that imsect, and so merely secured these two indi- 
viduals; though in all probability I might have easily 
obtained more, had it once occurred to me that it was 
distinct. 
The O. algicola is narrower and more oblong (or pa- 
rallel) than any of the Ochthebit which have hitherto 
been detected in these Atlantic islands, and except under 
avery high magnifying power it is totally devoid of all 
traces of even the minutest pubescence. With the ex- 
ception of its piceo-testaceous limbs, it is of a dark 
hue, being but very faimtly submetallic; its prothorax 
(which is, if anything, a trifle narrower than the widest 
part of the elytra) is free from any portion of pellucid 
margin (so common in the Ochthebi), and is very lightly 
impressed with an anterior and (curved) posterior trans- 
verse fovea; and its elytra are densely and coarsely 
striate-punctate, having almost the appearance at first 
sight of being subasperate and closely crenulated. 
(Sp. 223) Ochthebius subpictus. 
Madeira proper must be added to the habitat of this Och- 
thebius ; for although the individuals taken by myself in 
Porto Santo were all that had until quite lately been ob- 
served, a specimen has more recently been communicated 
by the Baron Paiva which was captured in Madeira. 
Being, in Porto Santo, found in streams which are brack- 
ish, it is not improbable that it may occur likewise in 
water which is almost, or even entirely, saline: at any 
rate in the same bottle which contamed it there are 
examples of the Calobius Heeri, which resides amongst 
marine Confervee in the small pools of actual sea-water 
(along the rocky shores both of Madeira and Porto 
Santo) ; and I cannot but think it likely, therefore, that 
this single Ochthebius subpictus may perhaps have been 
captured in company with the Calobii. 
Fam. HYDROPHILIDA. 
p. 77 (genus PHILHYDRUS). 
It is now more than a year since Dr. Sharp, who has 
studied the Huropean Philhydri with considerable care, 
detected some examples of Thomson’s P. maritimus 
