Terminology 127 



Explanation of Terms and Signs. 



Refer to Figures 115-138. 



For the sake of brevity and precision, we have adopted certain signs 

 and terms in our descriptions of Ixodidae, as follows : — 



3, $, o, L, signify male, female, nymph and larva respectively; rfs, <j?s and os 

 for plural. 



? after the names of parts, like Hypostome, Chelicera, Tarsus, etc., means that 

 these parts are missing in the type. 



L. = the extreme length of the tick, excluding the capitulum and legs. We prefer 

 to exclude the capitulum when measuring the length (from the scapulae to 

 the posterior border) because the capitulum is frequently injured or tilted 

 so as to render measurement difficult. 



W. = its width at the widest part. Where the measurements are given as xxy, 

 measurement x stands always for the length and y for the breadth. (I. and 

 w. refer to length and width of various structures.) 

 Capitulum = the "rostrum," "head" or "false head" of various authors. 



Basis capituli, or, shortly, base = the basal ring, "Kragen" of some authors. It 

 often shows a transverse elevated dorsal ridge with edge directed backward. 

 The ridge may have protruding angles ; the latter we term cornua. 

 There may also be a ventral ridge. The auricula signifies a protruding 

 retrograde process at the lateral angles of the ventral ridge posterior to 

 the insertion of the palps. When the length of the capitulum is given it 

 is measured from the tip of the hypostome to the dorsal ridge in the 

 median line. Where the dorsal ridge is absent it is similarly measured 

 to the ventral ridge. When the measurement is made ventrally this is 

 stated, the dorsal measurement being usually employed. The clear space 

 between the porose areas (only present on the £ capitulum) is spoken of 

 as the interval. 



Hypostome — the "maxilla," "radula," "labium," or " Unterkiefer " of various 

 authors ; a median ventral structure rising from the basis capituli, and 

 bearing recurved teeth. The dentition is indicated by figures on either 

 side of a vertical line. Thus 3 | 3 means three longitudinal files of teeth 

 on each half of the hypostome. The hypostome may be pointed, rounded, 

 or emarginated distally. It may be armed from tip to base with teeth or 

 only bear teeth along a part of its length. An unarmed, protruding median 

 ridge, which broadens basally, may run down the length of the hypostome, 

 starting near the tip. When a hypostome is described as having a corona, 

 the tip bears a number of very minute denticles. 



