ORIGIN OF THE NAME CHERMES or KERMES. 5 



have any power of condensing water vapour from the air, although naturally 

 any moisture condensed on the surface of a plant by a fall of temperature 

 may be taken in by them with their food. Grubs observed under the 

 microscope do not seem to swallow any of the moisture film condensed on 

 glass, although such moisture may be taken in through the general surface 

 of the body. A point worthy of mention is that the percentage of moisture 

 in a dried plant specimen is rarely uniform throughout, and that the grubs 

 may be feeding and thriving on the moister parts of a specimen which 

 seems as a whole prohibitively dry. Nevertheless the experiments show 

 that reduced as are the moisture requirements of the larvae, thoroughly dried 

 specimens kept in dry air in which no condensation of moisture occurs at 

 any time are practically immune from attack. In this connection the absence 

 of anything capable of aiding in the condensation of water is of importance, 

 such as sugary gum and certain kinds of glazed paper. 



Note on the Origin of the Name Cliermes or Kermes. 

 By E. R. BuRDON, M.A., F.L.S. 



[Read 6th December, 1906.] 



Great confusion has arisen from the fact that there are two genera of 

 insects, both belonging to the Hemiptera, which bear the same name under 

 different spellings. One of these is the genus Chermes included in the family 

 Aphidse, while the other belongs to the Coccidse and is spelt Kermes. 

 According to Kirkaldy (1) there is yet a third genus of the Hemiptera which 

 bears this name, viz. that usually known as Psylla belonging to the family 

 Psyllidge. Kirkaldy, enforcing the rules of priority in nomenclature, states 

 that Psylla should be called Chermes, and that the name of the family ought 

 to be Chermidse instead of Psyllidse. 



I leave it for others to decide whether this statement is correct or not, but 

 even supposing that the correct name of Psylla is Chermes, it would, I 

 consider, be a great mistake to insist upon the observance of the laws of 

 priority in the present instance. The confusion between the Aphid Chermes 

 and the Coccid Kermes is already so great, that it is no easy work to disentangle 

 the literature relating to either genus. This difficulty has to some extent 

 been overcome by a sort of tacit agreement to accept the difference in spelling 

 as sufficient indication of the particular genus referred to. Chermes is used 

 by most authorities for the Aphid genus, and an extensive literature is to be 



