THE GENUS HABROTROCHA. 635 



//. clegans (Milne), which, however, has a narrower corona and 

 a still shorter foot. 



Habrotrocha insignis, sp. nov. 

 PI. 38, fig. 1. 



Specific Characters. Head and neck long, slender ; trunk 

 much stouter ; foot very short. Corona narrow, three-fourths of 

 collar width ; disks dorsally canted and separated by notch ; 

 pedicels rather high, slender, adnate. Upper lip undivided, rising 

 nearly as high as pedicels, centrally rounded, stiffened by rigid 

 bent rod of staple-like outline. Mastax far back ; rami with 

 three teeth each. Gullet long and looped. Brain remote from 

 antenna. Spurs short, acute cones, without or with little inter- 

 space. 



When crawling this species bears some resemblance to Habro- 

 trocha angusticollis (Murray), when the latter is seen out of its 

 case. The skin of the long head and neck is so smooth that it 

 has a somewhat bright and tight appearance. That of the 

 trunk is finely punctate or stippled along the longitudinal skin- 

 folds, which are distinctly marked, the four central extending 

 over the preanal segment. In well-grown examples the trunk 

 is somewhat long and so much stouter than the neck as to give 

 a somewhat swollen appearance. It gradually increases in size 

 up to the fourth central segment, the succeeding preanal seg- 

 ment being nearly as large, and the anal much smaller, and so 

 rapidly diminishing to the end of the short three- jointed foot. 

 The slender rostrum has rather prominent lamellae. In front 

 of the antenna is seen within the head a curious structure, which 

 may be likened to a thin, rigid rod bent into the form of a staple, 

 but which may be the thickened margin of a concave plate 

 having that outline. No similar structure has yet been detected 

 in any other species. When the corona is protruded this bent 

 rod or plate is seen to be external on the dorsal side of the upper 

 lip. The points of the uprights are now directed forwards 

 (having pointed backwards while the corona w T as hidden), and 

 the closed end to the rear, about level with the anterior margin 

 of the base of the retracted rostrum. In dorsal view the uprights 

 diverge very slightly, the points reaching the anterior edge of 

 the upper lip on each side, not far from the centre. In lateral 



