244 MONOGRAPHIA 



The following species are enumerated by Nitzsch and 

 Burmeister. 



3. PHYSOSTOMUM IRASCBNS. (Louse of the Chaffinch.) " Pallide tes- 



taceum, margine abdominis externo ferrugineo ; occipite utrinque acu- 

 tissimo, longissimo." Long. 1. {Burmeister.') 



Physostomum irascens. Nitzsch. Germ. Mag. iii. p. 302. Step. Cat. pt. ii. 

 p. 335. Burmeister Handbuch ii. pt. ii. p. 442. Pediculus Motacilla. 

 Fabr. Syst. Antl. 349 ? Stew. Elein. ii. p. 300. ? 



4. PHYSOSTOMUM FRENATUM. (Louse of the Wren.) Album, capitispro- 



notique stria intramarginali, abdominisque margine-nigris. Long. 1|. 

 Physostomum frenatum. Burmeister Handbuch ii.pt. ii. p. 442. 



5. PHYSOSTOMUM SULPHUREUM. (Louse of the Golden Oriole !) " Sul- 



phureum, capite biplagiato, margine "bmni linea intramarginali nigra. 

 Long. 1|, (Burmeister}. 



Physostomum sulphureum. Nitzsch. Germ. Mag. iii. p. 302. Burmeister 

 Handbuch ii. pt. ii. p. 442. Children in Back's Land. Expe. Appendix, 

 539. Pediculus dolichocephalus. Scopol. Ent. Carniol. 382. n. 1039. 

 Pediculus Orioli. Fabr. Gen. Insect. 309. Syst. Inst. ii. 479. 19. 



6. PHYSOSTOMUM NITIDISSIMUM. (Louse of the Yellow Bunting.) 

 Physostomum nitidissimum. Nitzsch. Germ. Mag. iii. p. 302. Step. Cat. 



pt. ii. p. 335. Nirmus pterocephalus. Olfers. 91. Ricinus Fringillae. 

 De Geer. Inst. vii. tab. 4. fig. 6. 



GENUS II. GYROPUS. (Nitzsch.) 



Gyropus. Burmeister. Pediculus. Linnaeus. Schrank. Fabricius. Olfers. 

 GENERIC CHARACTER. 



HEAD depressed, scale-like, horizontal, frontal and tempo- 

 ral margin deeply sinuated, mouth anterior. 



MANDIBLES without teeth. 



MAXILLJE obscure. 



LABRUM and LABIUM produced, trapezoidal, entire. 



MAXILLARY PALPI long, produced, rigid, conical, and 

 4-jointed. 



LABIAL PALPI none. 



