SYSTEMATIC 487 



M. tuberculatus, Plate ; M. sattleri, Eichters ; M. papillifer, Murray ; 

 J\L coronifer, Eichters ; M crpnulatus, Eichters ; M. liarmswortM, 

 Murray; M. orcadensis, Murray; M. islandicus, Eichters ; M. dispar, 

 Murray ; M. anibiguus, Murray ; M. pullari, Murray ; M. hastatvs, 

 Murray; 31. du'bius,M.ui-va,j; M. echinogenitus,'Richters ; M.ornatus, 

 Eichters ; M. macronyx ? Doy. 



4. Genus DO YEBIA. — The teeth of ■ this genus have no 

 support, and the large salivary glands of the foregoing genus are 

 absent ; in other respects Boyeria, with the single species Boyeria 

 simplex, Plate, resembles Macrobiotus, and is usually to be found 

 in consort with M. hufelandi, C. Sch. 



5. Genus BIPJSASCON resembles M. oherhcluseri, Doy., but 

 an oesophagus separates the mouth-tube from the sucking pharynx, 

 and the oral armature is weak. The following species are 

 British, the first named being very cosmopolitan, being found 

 at both Poles, in Chili, Europe, and Asia : B. chilenense, Plate ; 

 B. scoticuvi, Murray ; B. buUatum, Murray ; B. angustatum, 

 Murray ; B. oculattim, Murray ; B. alpinmn, Murray ; B. spitz- 

 hergense, Murray. 



6. Genus MILNE8IUM has a soft oral armature, and the 

 teeth open straight into the mouth. A lens can usually be 

 distinguished in the eyes. Two species have been described, 

 M. tardigradum,, Doy., British, and M. alpigenum, Ehrb. Bruce 

 and Eichters consider that these two species are identical. 



