NEW PERIDINIACE.^. FROM THE ATLANTIC. 335 



and a border like that of the lateral sail ; upper margiii of i^irdle forming a long, 

 narrow, tubular funnel expanding sliglitly above and toothed at the edge ; distal 

 limb suppressed, and represented only by a minute membrane at the base of this 

 funnel. (PI. XXXIII. fig. 1.) 

 This singular organism occurs from lat. 23° N. in the Atlantic to Panama in the 

 Caribbean: 



HiSTioNEis MiTCHELLANA, sp. n. Proximal limb sbort and elongate in a dorsi-ventral 

 direction, deeper on the dorsal side, very faintly marked, bearing the sail on a 

 projecting semicircular thickened bar ; sail reticulate and forming two lateral flaps, 

 confluent on its ventral margin with the decurrent edge of collar ; proximal margin 

 of girdle forming a large wide collar, unmarked in the lower half, which expands 

 laterally, reticulate above, narrowing again laterally towards the top, where the edge 

 is entire, one side decurrent to the sail and reticulate ; distal margin forming a 

 narrow tubular funnel expanding and reticulate above, edge entire ; distal limb 

 suppressed, and represented only by a membrane at base of funnel. (PI. XXXIII. 

 figs. 'So, b.) 

 Prom lat. 31° N. to lat. 22° N. 



H. Helen/E, sp. n. Proximal limb short, stout, curved, with a row of distinct punctate 

 markings where it borders the girdle, parallel to a similar row on the girdle itself, 

 bearing on the ventral side the sail ; sail with faint reticulate markings on its outer 

 portion, which is so curved as to form a lateral flap, bearing also two unmarked, 

 rounded, opposite wings inserted parallel and near to the collar ; proximal margin 

 of girdle forming a collar, the upper part of which bears fine reticulate markings, and 

 its edge tine bristles at short intervals, one side decurrent to the sail ; distal margin 

 of girdle produced into a long tubular funnel expanding above, unmarked, and with 

 tine bristles projecting from the edge ; distal limb suppressed, and represented only 

 by a minute membrane at base of funnel. (PI. XXXIII. figs. 2 «, h.) 

 Prom lat 30° N. to lat 16^ N. 



H. DoLON, sp. n. Proximal limb short, stout, curved, very finely punctate, and 

 with a row of distinct punctate markings where it borders the girdle, parallel to a 

 similar row on the girdle itself ; bearing a large sail, which is so curved as to form 

 a large transverse hollow like a filled balloon-topsail, marked with parallel peri- 

 pheral lines, bearing also two opposite side-wings also hollowed, unmarked, inserted 

 near to and parallel with collar ; proximal margin of girdle forming a high collar 

 reticulate above, decurrent on one side to the sail and forming in fact an upper sail, 

 marked; distal margin prolonged into a long funnel expanding widely above, 

 unmarked except at the edge, where it is bordered by a band with fine vertical 

 markings ; distal limb suppressed, and represented only by a plate at base of funnel. 

 (PI. XXXIII. figs. 5 a, b.) 

 Found in lat. 28 X., long. 40 W.; and again in lat. 29° N. and long. 12'' to 44° W. 



