i6o 



HA RD WICKE'S SCIENCE- G OS SI P. 



satisfactorily as many of the generic characteristics 

 are sexual, and such weak characters as the colour of 

 the legs has been fallen back upon as distinguishing 

 points. 



One or two well-marked groups may be dis- 

 tinguished, (as Hydrotcca, Homaloniyia, &c.,) and 

 the principal genera may be recognised as follows : — 



Alulae of moderate size, scales of unequal size. 



Front femora in cf toothed, third and fourth longitudinal 



veins convergent : Hydrotcea, Des. 

 Front femora normal, third and fourth longitudinal veins 

 parallel or diverging. 

 Eyes pubescent : Hyetodesia, Rond. 

 Eyes bare. 



Abdomen spotted. 



Arista feathered : Spilogaster, Mcq. 

 Arista pubescent or bare : Limnophora, Des. 

 Abdomen unspotted. 



Anal vein nearly reaching border of wing. 

 Arista leathered : Hydrophoria, Des. 

 Arista pubescent or bare: Anthomyia, 

 Mg. 

 Anal vein very short, curved towards the 

 axillary vein ; Homalomyia, Bouch^. 

 Alula small ; scales of equal size. 



Arista feathered : Hylemyia, Des. 



Arista pubescent or bare : Chortophila, Mcq. 



Limnophora, Des., comes chiefly from Scotland. 



Hydrotaa dentipes, F., is a dark grey fly, with 

 greyish reflections ; pale brown wings ; black legs 

 and silvery cheeks, and is common in most parts ; 

 variable ; long 9 mm. 



D)yincia hamata. Fall., may be easily recognised 

 by its strong hooked proboscis. 



Hylemyia strigosa, Y., is a bristly grey fly, the 

 dorsum of the thorax being pale brown, distinctly 

 marked off from the lower part of the thorax ; 

 abdomen grey, with a dorsal and three transverse 

 black stripes ; face silvery seen from above, black 

 viewed from below ; mouth and antennae black ; 

 eyes reddish-brown ; wings pale grey ; legs blackish, 

 tibix more or less dark tawny ; common, especially 

 in woods ; variable ; long 6 mm. One species {^H. 

 coarctata. Fall.) damages the wheat crop whilst in 

 the larval state, attacking the stalk. 



Anthomyia radicutn, L., jf, is a small black fly, 

 breeding in cabbage and other like plants ; abdomen 

 dark grey, with a dorsal and four transverse black 

 stripes ; face and legs black ; wings pale grey ; eyes 

 often with a silvery border ; very common on low 

 herbage and in London gardens ; long 4 mm. 



A, szdciventris, Zett., is also common everywhere, 

 the (f is a nearly black fly, with unmarked abdomen. 

 The 5 is greyish-black, with unmarked abdomen. 



Caricea tigrina, F., common in long grass ; bristly, 

 grey with rows of black spots on the thorax, each 

 giving forth a bristle, and with four brown spots on 

 the abdomen ; legs black with tawny tibire ; face 

 grey with a broad central stripe ; eyes and antennte 

 black ; wings pale grey ; variable ; long 5-6 mm. 



Chortophila, Mcq., an extensive genus of small 

 flies allied to Anthomyia, many being tolerably 

 common ; some of the species being parasitic on 

 wild bees. Dr. Meade having taken them in the nests 

 of the latter. 



Homalomyia caniciilaris, L., is very common in 

 houses ; ^ blackish-grey ; abdomen tawny, divided 

 by a dorsal and two transverse lines into six squares, 

 tip blackish ; face silvery white, with a central black 

 stripe ; wings pale grey ; legs blackish ; variable ; 

 long 4-5 mm. The males of this genus hover 

 together in the air in a group, sometimes for hours 

 together, and are often seen in rooms in early morning 

 hovering below the centre of the ceiling or near the 

 windows. 



This species and another of this genus have been 

 bred from the human body. 



Hylemyia coarctata. Fin., in the larval state does 

 considerable damage to the wheat crop. 



The larva of Ca:nosia, Mg. (allied to Caricea), 

 lives in cow-dung. 



Over a dozen genera are represented by only one 

 or two species each. In several of the less developed 

 genera the eyes are widely separated in both sexes, 

 thus approaching the acalypterate Muscidce, from 

 which they are scarcely structurally distinct. 



Plates are not of much value in this group, except 

 to illustrate genera or very characteristic species. 



Hydrotcza ciliata, F., Curt. 768. Lispe tetitaculata, 

 Deg., Walk. ii. PI. xii. i. Anthomyia pliivialis, L., 

 Walk. ii. PI. xii. 2. Policies lardaria, F., Walk. ii. 

 PI. xii. 9. Dryvieia hamata. Fin., Walk. ii. PI. xii. 

 12. 



(To he continued.) 



A NEW SPECIES OF DASYDYTES— ORDER 

 GASTROTRICHA. 



THIS Order of the mighty worm-alliance seems 

 to have attracted very little, if any, careful 

 observation in this country of late years, although 

 both on the Continent and in the United States a 

 great amount of attention has been devoted thereto. 

 Quite recently, in 1887-8, Mr. A. C. Stokes added 

 greatly to our knowledge of the American forms, 

 describing in his papers in the "Journal de Micro- 

 graphie," numerous new species of Chietonotus and 

 other genera ; while in 1889, Dr. Carl Zelinka pub- 

 lished an exhaustive monograph of the group ( " Die 

 Gastrotrichen," in " Zeitschr. f. wiss. Zool.," xlix., 

 Part 2), in which all Stokes' recent species are 

 included, and to which admirable work I can con- 

 fidently refer British microscopists desirous of ex- 

 tending their acquaintance with these creatures. 



In our own country, Mr. T. Spencer described, in 

 " Journ. Quekett Micro. Club," January 1890, under 

 the name of Polyarthra fusiformis, an animal 

 which, however, is not a rotiferon, but (as pointed 

 out by me in the same Journal, January 1891) clearly 

 referable to the genus Dasydytes of the Gastrotricha. 

 This must evidently be known in future as Dasydytes 

 fusiformis, Spencer ; it is a pretty and curious little 

 creature, very distinct from any previously described. 



