526 MOSQUITOES OF NORTH AMERICA 



Janthinosoma Theobald, Mon. CuUc, iv, 148, 152, 1907. 



Psorophora Theobald, Mon. Cullc, iv, 148, 158, 1907. 



Grabliamia Theobald (in part), Mon. Culic, 150, 284, 1907. 



lanthinosoma Autran, Anal. Dep. Nac. Hig., xlv, 11, 1907. 



Psorophora Autran, Anal. Dep. Nac. Hig., xlv, 15, 1907. 



Psorophora Dyar & Knab, Can. Ent, xxxix, 48, 1907. 



Aedes Dyar £ Knab (in part), Can. Ent., xxxix, 48, 1907. 



Psorophora and Janthinosoma Howard, Osier's Modern Medicine, 1, 372, 1907. 



Psorophora Williston, Man. No. Am. Dipt, 3 ed., 108, 1908. 



Aedes Williston (in part), Man. No. Am. Dipt., 3 ed., 108, 1908. 



Janthinosoma and Psorophora Peryassfl, Os Culic. do Brazil, 34, 1908. 



Janthinosoma and Psorophora Pazos, San. y Ben., ii, 40, 1909. 



Orabhamia Pazos (in part), San. y Ben., ii, 40, 1909. 



Aedes Pazos (in part), San. y Ben., ii, 43, 1909. 



Janthinosoma Theobald, Mon. Culic, v, 112, 118, 1910. 



Psorophora Theobald, Mon. Culic, v, 112, 123, 1910. 



Orabhamia Theobald (in part), Mon. Culic, v, 116, 277, 1910. 



The type species are: Of Psorophora Eobineau-Desvoidy, Culex ciliata 

 Fabricius ; of Janthinosoma Ambdlzaga, Culex discrucians Walker ; of Orai- 

 hamia Theobald, Culex jamaicensis Theobald ; of Oonchyliastes Howard, Culex 

 musicus Say ; of Feltidia Dyar, Culex jamaicensis Theobald ; of Ceratocystia 

 Dyar & Knab, Culex discolor Coquillett; of Lepidosia Coquillett, Culex cyan- 

 escens Coquillett. 

 Genebic Diagnosis of Adttlt: 



Proboscis moderate; palpi short or moderately long in the female, never more than 

 half the length of the proboscis; those of the male longer than the proboscis. Head 

 elongate, the occiput broad and exposed. Antennae of the female filiform, the joints 

 subequal, with basal whorls of sparse, rather short hairs; those of the male plumose, 

 the last two joints long, the others short and thickened at the insertions of the hair 

 whorls. Prothoracic lobes remote dorsally, the prothorax produced Into a collar- 

 like neck. Mesonotum projecting anteriorly, arcuate, with setae on the disk. Scu- 

 tellum trilobate. Clypeus and i>ostnotum nude. Abdomen subcylindrlcal In the 

 female, tapered at the tip, the cerci prominent, the eighth segment entirely mem- 

 branous and completely retractile; that of the male elongate, depressed, with abun- 

 dant lateral cillation. Wings rather narrow in some species, broad in others; smoky 

 in most species, particularly towards the costa. Legs moderate, the hind tibial 

 scraper with a row of spines. Claws of the female toothed or simple; unequal and 

 toothed, at least in part, in the male. 



Geneeic Diagnosis op Laeva: 



The larvse divide into two groups which show striking differences correlated to 

 habits. The larvae of the one group, which constitutes Psorophora in the sense here- 

 tofore recognized, are predaceous; those of the second group, the subgenus Janthino- 

 soma feed in the ordinary manner upon small particles suspended in the water. The 

 adoption of the predaceous habit has led to a profound modification of the entire 

 head in the first group and the two subgenera are best defined separately. 



Subgenus Psorophora: Head broad, subquadrate, broadest at or behind the eyes. 

 The mouth brushes are well separated, inserted upon lateral prominences of the 

 front; the elements of the brushes are coarse, hooked at the apex and serrate along 

 their inner margins. Antennae small and inserted well back on the sides of the head. 

 The maxillae are broad, quadrate. Head hairs small, single. Lateral comb of the 

 eighth segment of many scales in a single row, sometimes attached to a plate, in 

 most species preceded by a large patch of minute rudimentary scales. Air-tube 

 somewhat fusiform, usually rather long, the pecten teeth produced into hairs and 

 followed by a hair-tuft Anal segment completely ringed by the chltinoua plate; 

 ventral brush well developed and extending into the plate. Anal gills four, equal. 



Subgenus Janthinosoma: Head rounded, rather broad. Mouth brushes normal in 

 position, composed of fine hairs. Antennae inserted upon prominent anterior angles 

 of the head, of moderate or large size, in one species Inflated, the tuft near the middle. 

 Maxillae prominent conical. Head hairs variously developed. Lateral comb of the 

 eighth segment of a few large scales usually attached to a weakly developed plate; 

 the scales are broad and fiat and have several large spines. Air-tube large, inflated 

 in all but one species, with only a few broad pecten teeth. Anal segment ringed, 

 ventral brush well developed and extending into the plate. Anal gills four, variously 

 developed, nearly obsolete in the salt-water species. 



