191(5.] 177 



H. i/fenensis is the only kind known in HelopJiorus to possess 

 abbreviated wings, and the phenomenon is equally rare among other 

 water-beetles ; it is in fact only known in a single Dytiscid : this little 

 and obscure Helophorns is therefore a very interesting creature. 

 Bradeniplenrns schmidti and Atracthelophorus hrevitarsis have reduced 

 wings, but are not aquatic. 



H. yfenensis is not yet known to occur in continental or Scandi- 

 navian Europe. In Britain I believe it to be an abundant insect, 

 though at present it has been recorded from but few localities. I 

 have examined specimens from North Cornwall (Padstow, Lamb), 

 the Isle of Wight (Totland Bay, Champion) , Brockenhurst (Bedwell, 

 Willoughby Ellis, Sharp and Walker), Cumberland (Day), Dumfries 

 (Irongray, Sharp), and North Ireland (Co. Down, Balfour Browne). 



{To he continued.) 



DIAGNOSIS OF A NEW SPECIES OF lUBLOPLECTUS 



(COLEOPTERA, PSELAPHIDAE). 



BY D. SHARP, M.A., F.R.S. 



Mr. H. Britten, who is engaged on an attempt to elucidate our 

 British species of this much misunderstood genus, has asked me to 

 publish a form he has not become acquainted with, except by means 

 of our specimens. 



Bihlojplectus margarefae sp. n. 



Piceus, antennis 2>edibusque testaceis, prothorace elytrisque i^arum clongatis, 

 illo 2)osterius bene angustato, his ad humeros angustis. Long, vix ultra 1 mm. 



Hob. : Brockenhurst, Angliae mer. 



The members of this genus are easily distinguished from Euplectus 

 by the absence of the anterior thoracic depression. Up to the present 

 time we have only recognised two species in Britain, viz., minutii^sinius 

 and amh'ujuus. B. margaretae has but little resemblance to the former, 

 but is closely allied to the latter, from which it may be sepai-ated by 

 the points mentioned above, though the real characters are to be found 

 in the extraordinary structure of the aedeagus, which differs from all 

 the others by the long slender process at the prow of the scaphium, 

 or bulb. 



Tliis species was discovered and dissected, and its characters 

 delineated, by my daughter, Margaret Annie Sharp, after whom I have 

 named it. I need say no more about it at present, as Mr. Britten will 

 deal with it fully, I hope, very soon. 



Brockenhurst : 



July rsth, 1916. 



