Ou some Mallophaga. 27 



dlhidus P., tlie 'pustule' will not shew against tlie prevailing white 

 of the background. but whenever this is darkened the 'pustule' be- 

 comes evident (semisignatus) or very pronounced as in the examples 

 from Faroe. 



Docox)horus troglodytis it. si).? Denny? 



Along with Menonon, Dr. Dampf took on Troglodytes horealis a 

 Single immature example of the peculiar Docophorus found on the 

 AVren. With this insect we have been long familiär from the Shet- 

 land variety of the host. In 1912 we noted it in the Denny coUec- 

 tion (3 examples with the name Hroglodytis'' merely marked at the 

 side) bat its position there suggested that it was not in the original 

 collection and Denny liimself has described nothing like the present 

 insect. On being appealed to Mr. Cummings writes that there is no 

 M. S. name for this form in the Denny Collection which contains 

 three examples (two headless) now mounted separately. They are 

 labelled simply ^'troglodytis''. 



We have hesitated hitherto to describe the Wren Docophoriis 

 becaiise of its strongly Nirmoid facies and also because Nirmus 

 gidosiis N. has been recorded from Wren. We imagine that gidosus 

 is really a Docophoriis very close to the insect now nnder discussion. 

 Mr. Cummings has kindly forwarded Nitzsch's original description 

 from the "Zeitschrift für die gesammten Naturwissenschaften", 1866, 

 p. 117, as follows ; ^'N. albidus prora flavescenti, pidiira praeter limbum 

 marginalem nidla. Capite cordato-triangtdari postica prothorace tripla 

 latiore, fronte trimcato ohtuso; abdominis elliptici pilosi sidco dorsali 

 nullo. Habitat in Certhia familiart\ 



Giebel Ins. Epiz. p. 140 adds "Die beträchtliche Breite des 

 herzförmigen Kopfes und dessen gerade abgestutztes Vorderende ge- 

 nügen schon, diese Art von allen vorigen der Singvögel zu unter- 

 scheiden". 



Piaget (Les Pediculines p. 162) further quotes Giebel to the 

 effect that N. gulosiis has three hairs at the side of the clypeus 

 while the 5th antennal Joint equals the 4th. 



Now in the wren DocopJwrus the head is in both sexes distinctly 

 longer than broad; the anterior edge of the clypeus is definitely 

 concave and there are some half dozen hairs at the side of the 

 forehead though the most anterior are not conspicuous. The 4th 

 ■antennal Joint is much shorter than the 5th. The head is at most 

 only twice the breadth of the prothorax. Therefore we prefer at 



