2 Dr. & the Kev. S. Graliam Biade-Biiks— 



liavc been recoided as luiuiiioiis \vc are not now concerned, 

 and paiu()i)()ds and synipliylcs are not known to produce 

 lif^lit. Among tlie centipedes, which have some attinities 

 with insect-, only one great gronp — the (ieophihjinorpha — 

 is known to exhibit the phenomenon with which the present 

 stndy deals. 



The elongate body of a Geophilomorph (fig. 1) consists 

 of a head and a lar;;e luimber of sul)siniilar segments, each 

 ])nt the last of which bears a pair of walking-legs. Each 

 leg-bearing segment is more or less flattened dor.-ally, 

 vcntrallv, and laterally, the dorsal and ventral snrfaces 



Fig. 1. 



Geophilus c<irj)oph(i(/us, Lcacli, d" , X 50, collected at Ihirwen, 

 Lancashire, July 11)19. II. K. B.-B. ad iiat. del. 



being snbequal and wider than the lateral snrfaces. The 

 legs arise from the external margins of the ventral surface, 

 and the stigmata, or breathing-pores, are found ou the 

 lateral surfaces. The integnment of each segment is 

 snp[)orted by a scries of chitinons jjlates, some of which have 

 been used by M. Henry W. 15rolemann (3), the eminent 

 French myriapodologist, for jjnrjjoscs of classification. 

 Characteristically the ventral surface possesses one median 

 unpaired })late (the sternite), and the dorsal surface has 

 two unpaired jjlatcs (a ])()steiior tcrgite and an anterior i)re- 

 tergitc). In front of the sternite is a pair of plates (the 

 ])resternal plates), wliicli in certain cases meet and fnse in 



