498 J* Bi KEYS: 
research there need be little doubt, as the writer has seldom ventured into 
a locality previously unknown to him without having been rewarded by 
the capture of one or more species new to the district. 
The obscure and unobtrusive habits of Beetles must in this connection 
be remembered. These characteristics, taken in conjunction with the 
fact that many species abundant in a favourable season may not be dis- 
coverable at all in the following year, render it desirable that likely places 
should receive frequent visits at suitable intervals, if the local Coleop- 
terous Fauna is to be completely enumerated. 
The absolute failure of the compiler to secure in the Plymouth area even 
a single exponent of the genus Alediws—and consequently of the genus 
Dyschirius which preys upon it—the ubiquitous D. globosus excepted— 
has long been a source of regret to him, and he cannot but think that 
they will yet be found in one or other of the creeks in the district, 
and particularly so as more than one member of both the genera have 
been taken in numbers at Dawlish Warren on the one side, and at several 
places in Cornwall on the other side of Plymouth. 
Of the truly Maritime and Sub-Maritime Coleoptera there is little 
doubt as to the species which should be included in such a list as the 
present ; but with respect to coast species the matter is not so readily 
determined. The main cause of doubt lies in the fact that the life-histories 
of so many beetles are not yet understood, and experience seems to show 
that species peculiar to the coast in one district are equally at home 
inland in another. A hard and fast line of demarcation in the matter of 
habitat is therefore not yet possible. But inasmuch as it is desirable to 
have authority in support of one’s ruling, the writer, in the main, has 
adopted Fowler’s Coleoptera of the British Isles as the guide for the 
inclusion of the coast species. A little discretionary power has been 
reserved however, and a few interesting species which occur with us 
only on the coast have been inserted in the list, although not definitely 
asserted by Fowler to be of that habit. 
One must not omit to record the successful work of Commander 
J. J. Walker, R.N., at Whitsand Bay in the seventies and early nineties. 
With him rests the honour of having first discovered there such rarities 
as Harpalus tenebrosus and Psammobius porcicollis, as well as a long list 
of other uncommon Coleoptera, and the writer heartily acknowledges his 
obligation to Commander Walker for kindly having shown him the 
habitats of those species. In later years Mr. Philip de la Garde, R.N., 
did splendid work in the South Devon District, and several additions 
were made to the British List by him; but perhaps his most notable 
contribution to the local fauna was the capture at Dawlish of the 
much-desired Arena octavi. It will be long ere the lamentable breach 
caused by his untimely death can possibly, if ever, be filled. 
