HYDROPHORUS. 



185 



slightly brassy, with black pubescence above. Legs dark green, with 

 black pubescence, tarsi black ; fore coxae with yellowish pubescence. 

 The distinctive characters are as follows : 



H. bipunctatus. 



Face above burnished, gilded 

 green, or sometimes steel-Hue in 

 the male, beloio dull yellotc, the 

 limit defined. Black cilia of the 

 orbit continued all round. 



Lamella of male attenuated at 

 each end, blackish-brown at the 

 tip, paler towards the base. Fourth 

 ventral segment compressed, trun- 

 cated behind, immaculate. Fore 

 coxae unarmed. 



Fore femora in male with a row 

 of short spines beneath from the base 

 to the middle, and a few still smaller 

 ones near the tip ; the tibia hairy 

 inside, withsome very minute spines 

 interspersed. In the female the 

 fore femora have only one or two 

 minute spines towards the tip, and 

 sometimes a single one near the 

 base, and the tibia is not hairy 

 inside. 



//. binotatus. 



Face above tarnished, brassy- 

 green, below glossed with white in 

 male, yellowish in female, the limit 

 undefined. Black cilia of the orbit 

 not descending as low as the pe- 

 ristoma. 



Lamella of male shorter, obtuse, 

 blackish-brown. Fourth ventral 

 segment scalloped at the end, with 

 the two intermediate teeth tipped 

 ferruginous. Fore coxas with a 

 few black bristles at the tip. 



Fore femora in male with a row 

 of short spines beneath, and a set 

 of longer ones close together, with 

 a blunt tooth in front of them, be- 

 fore the tip ; the tibia has a tuber- 

 cle in front at the base, and is mi- 

 nutely pectinated inside, indis- 

 tinctly so in the first half. In the 

 female the fore femora have a few 

 minute spines in a row near" the 



base. 



Obs. The description and habitat of Musca ungulata in the 

 ' Fauna Suecica' applying to either species indifferently, that trivial 

 name, if retained at all, belongs by right to the last, the other 

 having been the first satisfactorily characterized under another 

 name. According to Zetterstedt, H. linotatus is the more 

 northern and alpine species, ascending to the summits of the Alps 

 of Lapland : in Mr. Haliday's collection is a specimen found at 

 a height of 6000 feet on the Swiss Alps. 



7. balticus, Mg. iv. 66. 12 (1824) ; ZiLlitorem p., Fin. Oli- 

 vaceus, subtus cinereus, abdominis dorso anescente nigro-pubescente, hal- 

 teribus pallidis, hypostomate infero albido, Mas. ; aut lutescente, Fcem. 

 Long. I-*- ; alar. 5 lin. 



Front opake blackish-brown. Face greenish-brassy, below glossed 

 with white in male, yellowish in female. Cheeks expanded under the 

 eyes ; beard yellowish. Arista black, not so short as in those which 

 follow next, capillaceous only at the very tip. Thorax above olive-brown, 

 faintly striped, below yellowish ash-colour. Wings hyaline, usually 

 brownish in front ; the veins black, the costal vein from the darkness 



VOL. i. 2 B 



