A HISTORY OF HERTFORDSHIRE } Tring Haliplus mucronatus, Steph. Hertford (Ste- phens) flavicollis, Sturm. Wihtone, in the reservoir fulvus, F. Wigginton variegatus, Sturm. Wihtone, rare, in a stream cinereus, Aub6. Miswell, in the pond ruficollis, De G. Tring fluviatilis, Aub6. Wihtone lineatocollis, Marsh. Near Flaunden, rare Cnemidotus impressus, F. Hertford (Stephens) DYTISCID.E NOTERINA Noterus clavicornis, De G. Hastoe Laccophilus interruptus, Panz. obscurus, Panz. HYDROPORINA Hyphydrus ovatus, L. Hastoe Caelambus versicolor, Schall. scarce, in the reservoir inaequalis, F. Tring parallelogrammus, Ahr. Wihtone, in the reservoir Deronectes depressus, F. Wihtone 1 2-pustulatus, F. Little Tring, in the canal Hydroporus lepidus, Ol. Tring dorsalis, F. Wihtone, in the reservoir lineatus, F. Hastoe and Wigginton scalesianus, Steph. Boxmoor (Piffard). It is a great pleasure to be able to record this species for the county, as it seems so very restricted in its dis- tribution 1 angustatus, Sturm. Wigginton gyllenhali, Schiod. - palustris, L. V Tring erythrocephalus, L. ' memnonius, Nic. Ashridge Park and near Flaunden nigrita, F. Wigginton Common discretus, Fairm. Wihtone, in the reservoir pubescens, Gyll. Wigginton planus, F. Tring marginatus, Duft. Tring, one speci- men only of this rare insect taken in 1893 ; Hemel Hempstead (Pifhrd) DYTISCINA Agabus guttatus, Payk. Wihtone, in the reservoir 1 Originally taken by Mr. Scales in Norfolk, but the locality has been lost ; it appears to be only found now in Askham Bog near York (Fowler, British Coleoptera, vol. i.). DYTISCINA (continued) Agabus didymus, Ol. Wigginton and Little Tring nebulosus, Forst, Little Tring, in the reservoir sturmii, Gyll. Wigginton chalconotus, Panz. Tring, in the reservoirs bipustulatus, L. Tring Platambus maculatus, L. Wihtone, scarce, in a stream Ilybius fuliginosus, F. Wigginton Common fenestratus, F. Wigginton Common ater, De G. Mhwell and Wigginton Common obscurus, Marsh. Wigginton Common Rhantus bistriatus, Berg. Mis-well, in the pond Colymbetes fuscus, L. Wihtone, in the reservoir Dytiscus punctulatus, F. Near Totternboe (Piffard) 1 marginalis, L. Hastoe Acilius sulcatus, L. Wigginton Common and Wihtone GYRINID^E Gyrinus natator, Scop. Tring HYDROPHILID^E Hydrobius fuscipes, L. Tring Anacaena globulus, Payk. Little Tring and Wihtone limbata, F. Wihtone Philhydrus testaceus, F. Wihtone, rare, in the reservoir coarctatus, Gredl. Wigginton Cymbiodyta ovalis, Thorns. Wihtone, scarce, in the reservoir Helochares lividus, Forst. "| _. . Laccobius sinuatus, Mots. / rm & bipunctatus, F. Wihtone Limnebius truncatellus, Thorns. Tring papposus, Muls. Wigginton nitidus, Marsh. Tring, one specimen floating on a water butt in garden HELOPHORINA Helophorus rugosus, Ol. Wihtone, not uncommon in ditches nubilus, F. Tring. This insect may often be found in numbers at the roots of grass, etc., on the hills aeneipennis, Thorns. > <_- . brevipalpis, Bedel. / * Hydrochus angustatus, Germ. Wigginton Common ; Hertford (Stephens) 1 Mr. Piffard has some doubts as to whether this capture was really made within the county boundary. 88
