776 DIPTERA OF AUSTRALIA, 



Entom. V. p. 394, tab, ii. f. 9-12, 1851 ; Geranomyia, Hal, Ins. 

 Brit. iii. p. 310, 1856; Plettusa, Pliilippi, V. z.-b. G. Wien, 

 p. 597, t. XXIII. f. 1, 1865 ; Geranomyia, O.-Sacken, Mon. Dipt. 

 N. Amer. lY. p. 78, 1869 ; Wulp, v.d.. Dipt. Neerl. p. 396, 

 t. XII., f. 5-6, 1877 ; O.-Sacken, Studies, II. p. 173, 1887. 



" One sub-marginal cell ; four posterior cells ; a discal cell. 

 Antenna3 14-jointed, sub-moniliform ; joints not pedicelled. 

 E/Ostrum and proboscis prolonged, longer than the head and 

 thorax taken together ] the short palpi inserted about their 

 middle. Feet slender ; tibiae without spurs at the tip ; empodia 

 indistinct or none ; ungues with teeth on the under side. The 

 forceps of the male like that of Dicranomyia, and consists of two 

 fleshy, movable lobes, with horny appendages and a horny style 

 under them." (Osten-Sacken). 



Four species which I refer to this genus differ in the number of 

 joints to the palpi ; one species has only biarticulate palpi, two 

 have them 3-jointed, whilst another has them 4-jointed. These 

 differences compel me to suggest the institution of three sub- 

 generic groups ; in other respects these insects do not more than 

 specifically differ from hitherto described Geranomyice. There 

 has always seemed some doubt about the number of joints to the 

 palpi. Haliday first of all believed them to consist of but one 

 minute joint. Baron Osten-Sacken takes them to be biarticulate 

 on the authority of Curtis ; but the latter author himself queries 

 the statement in his generic diagnosis. Having not a specimen 

 of any described species it is impossible for me to more than 

 surmise that upon careful examination the known examples, of 

 which the majority prevail on the American continent, will be 

 found to differ in the number of joints comprised in the palpi. 

 The type of the genus, G. unicolo7\ Hal., probably has, but 

 possibly may not have, only biarticulate palpi ; and Curtis errs 

 when he states that they are " attached to tJie anterior angles of 

 the mentum." They are in reality attached to the sides of the 

 labium below the point where the latter divides. The labium 

 with the palpi can be drawn away from the other organs upon 

 careful dissection. 



