760 DE. W. B. CAEPENTEE ON THE STBUCTTJEE, PHYSIOLOGY, AND 



Fig. 9. Central portion of fig. 2 more enlarged, showing the Rosette in situ : — a, a, lines 

 of junction of the First Radials ; h, b, apertures formed by the coalescence of 

 the spout-like processes of the Eosette with the inner margins of the First 

 Eadials. — Magnified 70 diameters. 



Fig. 10. Rosette separated and seen on its dorsal aspect, showing its five flattened trian- 

 gular processes, a, a, and its five intermediate spout-like processes, b, h. — 

 Magnified 100 diameters. 



Fig. 11. Rosette seen from the ventral side, showing around its central orifice irregular 

 projections which coalesce with the processes given-off from the inner margins 

 of the First Radials ; a, a, triangular processes ; b, b, spout-like processes. — 

 Magnified 100 diameters, 



PLATE XXXIV. 

 The following References are common to both Figures : — 



r\ r\ First Radials. 



r', r', Second Radials. 



r", r^, Third or Axillary Radials. 



br\ br\ First Brachials. 



br', br', Second Brachials. 



br', h^. Third Brachials. 



p,Pi Pinnules. 

 Fig. 1. Horizontal section of Calyx and basal portions of Arms of Antedon rosaceus, 

 flattened out ; showing the axial canals, a, a, of the Rays which communicate 

 by circular branches at b, b (as in Plate XXXIII. fig. 1), and bifui-cate at c, c, 

 to pass into the Arms. — Magnified 18 diameters. 

 Fig. 2. Interior of the Calyx with basal portions of Arms, of a young Antedon, to show 

 the disposition of the Muscles: — m\ m^, five pairs of muscles passing between 

 the First and Second Radials ; m^, nf, ten pairs of muscles passing between 

 the Third or Axillary Radials and the First Brachials ; vi^, m^, ten pairs of 

 muscles passing between the Second and the Third Brachials. — Magnified 30 

 diameters. 



PLATE XXXV. 



Fig. 1. Vertical Section of the Centro-dorsal Piece; consisting of the Centro-dorsal 

 plate which forms the dome of the cavity, and which is anchylosed at the 

 lines a, a, a, a to the First Radials ; b, b, canals leading to the articular sockets 

 of the cirrhi ; c, basal segment of a cirrhus ; d, d, axial canals of First Radials ; 

 e, e, portions of Second Radials; f, Rosette. — Magnified 70 diameters. 



Fig.' 2. Longitudinal Section of three of the basal segments of a Dorsal Cirrhus, showing 

 the central articular processes, and the ligaments interposed between their 

 peripheral surfaces. — Magnified 70 diameters. 



