D. BRYCE ON MACROTRACHELOUS CALLTDIN^. 449 



minent rostrum, and coat of dirt recall the like points of Call, 

 longirostris, with a suggestion of Call, aspera, which in size it more 

 nearly resembles. The skin-folds are not, however, wart-crowned, 

 but have their ridges broken by numerous transverse creases. 

 That the skin is viscid is proved by the coating of foreign matter 

 with which it is liberally covered, but the viscidity is confined to 

 the trunk. The head, neck, and foot are usually clean. Save on 

 the first foot joint, I could see no trace of the minute pores which, 

 according to Janson,* pour forth the viscid secretion in other 

 species. The transverse ventral folds are much less distinct than 

 in Call, alpium, but still sufficiently obvious. The corona is rather 

 small, and the discs approach each other vtry nearly, and have in 

 dorsal view a somewhat square outline. 



The first cervical segment has three almost lappet-like swellings 

 of the hypodermic layer, of which two proceed from the base of the 

 antennae towards the ventral side, attaining greatest size on the 

 dorso-lateral angle, and thus forming thickened and somewhat pro- 

 minent epaulets, and the third lies across the ventral surface just 

 below the mouth. When the corona is displayed, the sub-ventral 

 process is thrown outwards and backwards, and is distinct, either 

 in direct ventral or in lateral view. The lateral lobes correspond 

 to the fronto-lateral prominences of Call, longiro tris and some 

 other forms, but I know of no other species having the sub- 

 ventral swelling. I have thought that the function of all three is 

 to protect the more delicate parts of the head when the creature is 

 pushing its way among the sand-grains, which coat evin the 

 cleanest specimens of ground and wall moss, and 1 should accord- 

 ingly expect that all or most other species with these swellings 

 would be found principally among such mosses. It might be 

 further inferred that the species \\hich have developed these pro- 

 tective swellings are species of longer standing in their chosen 

 habitat than others which have not yet^cquired them. 



The antenna is rather short, but is stout and tipped with rather 

 long setas. The foot boss is more prominent and harder-looking 

 than usual, while across the anal segment there is a distinct dorsal 

 ridge, which appears to mark the limit of the non-invertile skin. 

 Specimens were exhibited at the meeting of the Club on 6th 

 October, 1893. 



Habitat. Wall moss from South Bersted, near Bognor. 



