232 MODERN SYSTEM. 



Geijus 304. LIVIA. Latr., Leach. Dirapiua. Illigcr. 

 Antenna shorter than the thorax, the base much thickened even to the 



middle : thorax with the anterior segment transverse, straiglit. 

 Sp. 1. Liv.juncorum. (PI. 5. fig. 11.) magnified: the line beneath exhi- 



bitx the natural size.) 

 Livia Juncorum. Latr, 

 Inhabits Junci. 



Fam. IV. Apiiid.1;. Leach. 

 Aphidii. Latreille. 



Tarsi two-jointed, the first joint very short : rostrum in both sexes : 

 antenna with six, seven, or eight joints : females generally apterous : 

 tarsi with the last joint vesiculous. 



Stirps 1. — Antenna eight-jointed : rostrum minute and horizontal with 

 indistinct joints : head elongate-quadrate. 



Genus 305. THRIPS. Linn., Geoff., Latr., Lam., Oliv., Leach. 

 Elytra and wings horizontal and linear. 



Sp. 1. Thr. Physapus. Black, hairy: antennae, tibise, and tarsi pale: 

 middle of the tibise pale brown; elytra and wings white. {PL 5. 

 ftg. 12. mugnifed : the line beneath shows the natural size.) 



Inhabits the blossoms of various plants. 



Stirps 2. — Antenna seven-jointed : elytra larger than the wings : ros- 

 trum subperpendicular, with three very distinct joints : /(e«f/ trans- 

 verse. 



Genus 306. APHIS. Linn., Fabr., Latr., Oliv., Lam., Leach. 

 Antenna setaceous or filiform, seven-jointed: elytra larger than the 

 wings; elongate triangulate: abdomen towards the apex generally 

 tuberculated or horned : eyes entire. {PL 5. ftg. 9.) 



The animals of this genus are very numerous, and are found on 

 almost every plant. The French call them Pucerons, the English 

 Plant-lice. The species require examination ; the plant on which 

 they arc found should be noticed, as it will aftord specific nancies. 

 The females are generally apterous. 



Genus 307. ERTOSOMA. Leach's MSS. 



Abdomen without tubercles or horns : antenna short and filiform : body 

 tomentose. 



" The Eriosomata form what arc called improperly Galls on the stalks 

 of trees near their joints, and knobs, which are in fact excrescences 

 caused by the efforts of nature to repair the damage done to the old 

 trees by the perforation of those insects, whose bodies are covered 

 with down." Leach's MSS. 



Sp. 1. Er. Mali. 



Aphis lanigera of authors, 



