Insects. 



8611 



7. H. granulans, Linn. The commonest species, and very variable. 



S. H. aeneipennis, Thorns. About the size of H. griseus, with the elytra sub- 

 aqueous and the legs darker; the interstices of the striae are also clearly more convex. 

 This species and the two preceding were united by Mulsant, in his 1 Palpicornes,' 

 under the name H. granulans, and it is very possible that they may be found 

 analogous to those found in Hydrobius globulus or Laccobius minutus. 



9. H. nanus, Sturm. Formerly taken in Cambridgeshire, I believe, but I have 

 never met with it. The smooth interstices of the thorax render it unmistakeable. 



10. H. quadrisignatus, Bach. This is the species which generally stands as 

 H. dorsalis in our collections; it is found, I believe, in brackish water near Gravesend. 

 The dilatation and pattern of the elytra sufficiently characterize it. 



11. H. arvonicus, Muls. All the specimens I have seen of H. pumilis of Erichson 

 belong to this species. The true H. pumilis is a much shorter and broader insect. 

 This may be recognised from our other indigenous species by the subcariuate iuterstices 

 of its elytra. 



While on the subject of Philhydrida, I may mention that I have identified as 

 British the Philhydrus frontalis of Erichson and P. ovalis of Thomson from types sent 

 me by Mr. Thomson. — G. R. Crotch. 



Description of two new Species of Mycetoporus. — 



Mvcetoforus longicornis, (M'dk/in, Symbol. 12, 11 ?) ; Kraatz, Ins. Deutschler. 

 ii. 467, 14. 



M. spleudidus, var. 2, Erichs. Gen. et Spec. Staph.. 287, 9. 



I have recently taken, near Croydon, an example of this species (hitherto, I believe, 

 unrecorded as British), and have since detected in Mr. Waterho use's collection four 

 other specimens, including one male, taken by him, at different times, near Erith and 

 Croydon. It is closely allied to M. splendidus, but differs from that species in the 

 following points: — In the first place, it is apparently always larger, somewhat flatter 

 and broader, the thorax especially being wider; and I may here remark that the un- 

 varying size of " one line " given by Kraatz for M. splendidus is evidently erroneous, 

 as I have seen examples of that insect sent over by Kraatz himself, and which are 

 precisely the same as our common species of that name, for which the smallest length 

 given (and correctly so) by Erichson is one line and a half. Besides the above- 

 mentioned differences of size and shape, M. longicornis also differs from M. splendidus 

 in having the joints of the antennae comparatively not quite so stout, with the ter- 

 minal joint more oblong-ovate, and in the punctuation of its abdomen on the upper 

 side being rather more remote. In colour also it differs very considerably, being more 

 uniformly rufo-lestaceous, with only a slight scutellar patch, and merely the base of the 

 abdominal segments (especially the fifth and sixth) more or less pitchy; whilst M. splen- 

 didus has the head and often the greater portion of the elytra, pitchy or even black, and 

 the abdomen more or less black, with the outer margins of the segments testaceous; 

 beneath, in both species the metathorax is dark (but blacker in M. splendidus), and 

 the under surface of the head is rufo-testaceous in M. longicornis, but black with the 

 gular area yellow in M. splendidus. The antennas, moreover, in M. longicornis are 

 altogether lighter in colour, the three first basal joints being especially lighter, whilst 

 in M. splendidus the first joint only is light. The principal distinguishing characters, 

 however, of the two species are to be found in the male of each ; in M. splendidus the 



