26 James Waterston, 



have become almost uniformly darkened save for the presence of 

 colourless pustules or a spiracle. In series of tj-pical semisignatus 

 from Perthshire; Forfarshire; Rossshire; and Shetland we have only 

 once Seen a specimen similar to these Faroe examples. Yet they 

 seem darker. 



Professor Kellogg (New Mallophag-a IL p. 477, tab. 65, fig. 5, 

 1896) described from Corvus corax sinuatus a Docophonis distinctus 

 which has since been reported from C. corax principalis. Beyond 

 the extremely dark markings, we cannot see any good character 

 to separate Kellogg's species from semisignatus. 



We had just put these notes into shape when through the 

 kindness of Captain Heddle, Grangemouth, we had an opportunity 

 of collecting D. semisignatus from a Eaven shot at Ronas Voe 

 11./8. 1913, also through the courtesy of Captain Jenssen, Manager 

 of the Alexandre Whaling Station Collafirth, we secured Bocopliorus 

 from another Raven shot near the Station, 1./9. 1913. Collafirth and 

 Ronas Voe are in the neighbourhood of Ollaberry, The Ronas Voe 

 bird was a j'ouiig one of the year — a large specimen, while the 

 Collafirth example was an adult — $? — snialler than any Shet- 

 land Raven we have seen. To our delight both lots of JDocophorns 

 taken are quite comparable with the dark Faroe material. The 

 onl}^ other Shetland examples of semisignatus we possess agree with 

 our Scottish material. Here mean time we must leave the matter, 

 Apparently D. semisignatus N., Z). albidus P., and D. distinctus Kel- 

 logg represent one species. We should call Dr. Dampf's lots b) and c) 

 and the Shetland examples just referred to, distinctus KblijOgg. But 

 whether distinctus is a geographical or a host or racial variety or merely 

 a very intensely marked phase of the adult Raven Bocopliorus 

 we cannot say. The best character for D, semisignatus — apart 

 from the male genitalia — would appear to be the peculiar signa- 

 ture with its well defined frontal margin and posterior (apical) 

 clear region. In distinctus the occipital bands stand brilliantly out 

 and the edge of the metathorax is plainly darkened. Kellogg has 

 already noted these points. But colour distinctions are so uncertain 

 as to be by themselves of no specific value. Too much stress also 

 may easily be laid on the presence or absence of "pustules in- 

 colorees". 



The majority of the stronger elements of the chaetotaxy have 

 probably a sensory connection. In any case the chitin of the area 

 on which they stand seems thinner. In a little coloured form like 



