A SYNOPSIS OF THE BRITISH SYMPHYLA 



a. 10 or II setae on lateral margin of second scutum 



between the an tero- lateral seta and the apical ; in- 

 cluding two prominent ones. isabellge, Grassi. 



b. Only 7 or 8 such setae, including three prominent ones, 



the third coming next to the apical seta. 



isabellse, Grassi, var. dunelmensis, Bagnall. 



2. Size usually smaller and more slender. The last pair of legs 

 with two long protruding setse on the metatarsus, and only 

 two or three in the anterior dorsal row on the tarsus. Cerci 

 not so long and less closely furnished with setse. 



a. Lateral margins of 2nd scutum angulate at about the 



anterior third ; inner margin of process with one 

 or two setae between the apical seta and the one at 

 the basal angle. 



aa. Cerci without long outstanding setse on either the 

 upper or lower margin. Setae on scuta ex- 

 ceptionally long, as long or almost as long as 

 the length of processes ; five on the lateral 

 margin of the second scutum between the antero- 

 lateral and apical setse, and one on the inner 

 margin of process. More slender. 



horrida, Bagnall. 



bb. Cerci with a few long outstanding setae on lower 

 margin only. Setae, excluding the antero- 

 lateral pairs, on scuta small ; second scutum 

 with about seven setae on the lateral margin 

 and two on the inner margin of process 

 between the setae above-named (« and ad). 

 Three setse on tarsus of hind leg. Less 

 slender. vulgaris, Hansen. 



b. Lateral margins of second scutum arcuate ; inner margin 



of process without any setae between those above- 

 named (a). 



aa. Size larger (2*5 mm.). Cerci with a few long 

 outstanding setse on both the upper and lower 

 margins. Setse on scuta, including the antero- 

 lateral pairs, very weak and minute ; only 

 four on the lateral margin of the second scutum 

 between the antero- lateral and apical setae. 

 Two setae on tarsus of hind leg. Very 

 slender. delicatula, Bagnall. 



