NEW PEEIDIXIACE.^ EEOM THE ATLANTIC. 331 



I'HALACROMA RrDGEi, sp. 11. Bodj Unequally divided by the girdle, with no markings, 



ovate in side view, of proportionately great breadth in ventral view, with broad flat 



suture-plates on both limbs ; proximal limb with narrow and short sail ; distal limb 



slightly arched. (PL XXXI. figs. 6 a, b.) 



It appeared only once in our collections, viz. in lat. 37 55' N., long. 36 42' W., 



where it was found by Capt. Rudge of the ' Avon.' 



DiNOPHYSis, Ehrenb. 



This genus abounds especially in the Atlantic between the Azores and Barbados* 

 D. Somunculus, Stein, occurred very constantly from lat. 48^ X. to Panama ; D. rotimdata. 

 Clap. & Lachm., from lat. 41^ X. to the Caribbean ; D. hast at a, Stein, occurred from lat. 

 41° X. to lat. 18° X. ; D. uracantha, Stein, from lat. 43 X. to Panama ; D. sphcBrica, 

 Stein, from lat. 44° X. to lat. 18 X. ; D. acuta, Elirenb., from lat. 49 X. to lat. 29" X. ; 

 D. Sacculus once only in lat. 41 30' X., long. 28 W. In addition to these we found one 

 new species, viz. : — 



D. RuDGEi, sp. n. Body globular ; proximal limb covered with very large circular pits, 

 and with a terminal spear-like appendage and a very small sail; girdle with 

 proximal margin produced and forming a transparent collar, and distal margin 

 prolonged into a short cylindrical funnel. (PI. XXXI. fig. 9 a, h.) 

 It occurred only on the voyage of the ' Avon ' in lat. 33 20' X., lon^. 43' 9' W. 



D. ScHUETTii, nob. 



In his ' PeridiniaceaB of the German Xational Plankton Expedition' (tab. ii. fig. 9). 

 Dr. Schlltt has figured under the name of Liyiophysis uracantha. Stein, a specimen 

 which, on comparison with Stein's figure (' Infusionsthiere,' pt. iii. tab. xx. figs. 22, 23), 

 presents manifest differences. We have found an organism (PI. XXXI. fig. 10) ao-reein"- 

 with Dr. Sehiitt's figure. It differs from _D. uracantha in the form of its sail and in 

 having no terminal spine, but with a process supporting a small, narrow membrane at 

 its base, placed on the dorsal side. We have separated it from D. uracantha under the 

 above name. 



Amphisolenia, Stein. 



A. palmata. Stein, occurs from lat. 38 X. to lat. 14 X., and A. Thrinax, Schiitt, from 

 lat. 29° X. to lat. 27 X. 



Another species, described below, which appears to be intermediate in the characters it 

 presents between A. palmata, Stein, and A. Thrinax, Schiitt (in * Pflanzenleben der 

 Hochsee,' p. 33), occurred in the same place and in the collections made by the ' Elbe.' 



A. BiFURCATA, sp. u. Proximal limb composing the body \ the distal limb composed of 

 two plates and reduced to a flat membrane ; margins of girdle expanded into 

 two frills equal in size and of like appearance ; proximal limb elongate, swollen to 



3c2 



