258 THE SCOTTISH NATURALIST 



that the tip of the head was creamy white, and that proximal to this 

 area the head was sm-rounded by a black band or "collar" about 

 0.2 mm. in breadth. 



The posterior end of the male was bifurcated, the branches 

 being about 0.5 mm. in length. There was no fold of cuticle 

 behind the cloaca, but it was bordered by a lateral series of short 

 bristles on each side, the two series of bristles converging towards 

 the median line in front, as in the case of Parachoniodes violaceus 

 (see Fig. 7). 



The cuticular pattern is very different from that of any other 

 species. There is, indeed, a series of very finely marked lines 

 beneath the surface, as in forms already described, but the surface 

 pattern appears to consist of refringent tubercles set in continuous 

 rows following the length of the body, and not in distinct circular 

 areoles. The rows are 13 /x to 15 /x apart, are slightly waved, and 

 the sinuosity tends to be regular, the curves in any two adjoining 

 rows bulging apart and constricting alternately. The rows may be 

 taken as forming the sides of a series of adjacent hexagons the tops 

 and bases of which are missing. In some cases, indeed, basal lines 

 are suggested by the presence of refringent lines, probably equivalent 

 to a series of united tubercles, connecting adjacent rows of tubercles. 

 The tubercles themselves when seen in side view, magnified 1000 

 diameters, arc exceedingly insignificant, being almost flush with the 

 general surface, and exhibiting nothing of the prominence character- 

 istic of those of, say, P. tolosanus. 



Distribution. — Only one previous record is known, from 

 northern China (Camerano, 1896, p. iiS). 



British Isles. — The solitary British habitat is that in which 

 the male specimen above described was discovered, in a spring at 

 OUaberry, Shetland, 24th August 1912, by Rev. Jas. Waterston, by 

 whom it was presented to the Royal Scottish Museum. 



(4) The Mottled Hairworm (Fig. 6) Gordius villoti 



(Rosa). 



In this species are included forms described under the name 

 Gordius aquaticus by several recent authors. Whether the modern 

 use of the specific name G. aqtcaticiis corresponds with that of 

 Linnoius, is a matter of grave doubt which it is now impossible to 

 dispel. The name, moreover, owing to different interpretation%-has 



