HYDROPHILID.^. 33 



From H. rugosus, 01. (for which we ought perhaps to substitute the 

 name H. rufipes, Bosc.) the species may be known by its average smaller 

 size, flatter dorsal costse of the thorax, and the fact that the elytra are 

 not sinuate near the base and have the humeral angles rounded, 

 whereas in H. rugosus the elytra are sinuate before the base, and the 

 humeral angle is turned outwards forming a distinct tooth; from 

 H. oiubilus, it is distinguished by its larger size, somewhat irregular 

 dorsal costse of the thorax, and the much more elongate second joint of 

 the maxillaiy palpi. The species, in fact, has longer and more slender 

 maxillary palpi than any of our other Helophori (v. Ent. Mo. Mag. 

 xliv. (2 Ser. xix.), 1908, 88). 



H. sequalis, Th., has always appeared to me to be a variety of 

 H. aquaticus, and is so regarded in the last European Catalogue. 

 H.crenatus ha.s only apparently been recorded as British by M. Pandelle 

 and has not been confirmed. Our information with regard to 

 ff. strigifrons rests where Blackburn left it in 1876, as Mr. Edwards 

 points out, and I have not seen any British example of the species. 



H. viridicoUis, Steph. ( = (cneipennis, Brit, Col.) is a very variable 

 insect, and in the European Catalogue has no less than twelve synonyms 

 under it, apart from three varieties, H. planicoUis, Thoms., is regarded 

 as a synonym, as well as //. obscurus, Rey. 



Since I wrote the above, Mr. F. Balfour-Browne has sent me the 

 following note : " I do not consider cequalis a good species, nor, in my 

 opinion, is strigifrons distinct from the very variable (eneij)ennis. 

 H. affinis and griseus are varieties of a single species, but II. brevicollis, 

 Thoms. (granular is, L., ?) is distinct. I have taken the latter lately 

 in Donegal West (Dunfanaghy), Co. Down, Mayo W., and recently 

 in numbei's in Co. Antr-im in one pool. There is a single specimen in 

 the Chitty collection at Oxford. Otherwise I have not seen British 

 specimens." 



H. viridicoUis, Steph., 111. Br., ii. 29 (= mieipennis, Thoms. = 

 obscurus, Rey.), var. shetlandicus, Kuw. Ver des Natur. Yer. in 

 Briinn, xxviii. p. 227. This variety, from the Shetland Isles, has the 

 elytra black, shining and metallic ; it is evidently one of the melanic 

 forms of insects which are found in northern localities [v. Donisthorpe, 

 Ent. Record xi., 1899, 184), 



This variety appears in the last European Catalogue, but is not 

 mentioned by Ganglbauer. 



H. brevipalpis, Bedel, Faune. Col. Bass. Seine, 1881, 301, 323, 

 var. bulbipalpis, Kuw., I.e. p. 196. This variety, also from the 

 Shetland Isles, has the last joints of the palpi so strongly thickened 

 that they almost appear to be deformed. 



In the Entomologist's Record, xi. 1899, 184, Mr. Donisthorpe 

 recorded this insect as a variety of //. griseus, and as such it was described 

 by Kiiwert, but it seems best to assign it to II. brevipalpis, Bedel. In 

 the last European Catalogue it appears merely as a synonym of //. 

 hrevi'jKiljAs, but Ganglbauer i-egards it as a variety of that species. 



c 



