DEVELOPMENT OF ANTEDOX (COMATULA, LAMK.) EOSACEUS. 751 



Fig. 3. Longitudinal section of the terminal portion of a Dorsal Cirrhus ; sliowing the 

 claw articulated by the plane surface cut through at «, «, to the penultimate 

 segment, and the movable articulation b, b, in which the fossae for the lodg- 

 ment of the ligament are much larger and deeper on the aboral side ; ai c, c 

 is shown the central canal, which is continued into the cavity of the claw. — 

 Magnified 70 diameters. 



Fig. 4. Section of Centro-dorsal plate taken in a plane parallel to its flattened surface ; 

 showing at b, b the canals leading to the articular sockets. — Magnified 

 70 diameters. 



PLATE XXXVI. 



In this Plate are shown the First, Second, and Third Badials, and the First, Second, 

 Third, Fourth, and Fifth Brachials, of Antcdon rosaceus ; their different aspects being 

 designated (except in fig. 1) as follows : — 



A, internal or proximal face. 



B, external or distal face, 

 c, ventral or superior face. 

 ]), dorsal or inferior face. 

 E, lateral face. 



The following lleferences are common to the entire series : — 

 a, a. Articular Ridges. 

 h, b, Fossae for Interarticular Ligaments. 



c, c. Muscular Fossse. 



d, d. Vertical Lamellae. 

 e, Axial Canal. 



f,f. Fossa for Elastic Ligament. 

 p. Articular Socket of Pinnule. 

 ^9^ Syzygy. 

 The magnifying power for all the Figures is 15 diameters. 

 Fig. 1. First Radial : on its internal aspect (b) are shown the apertures, e, e, of the two 

 passages by which the Axial Canal originates, and the apertures, ff, {/, of the 

 circular passage by which the axial canal of each Ray communicates with the 

 canal of the Ray on either side ; h, furrow between the prominent margins of 

 the apertures e, e ; ?', ?*, smooth inclined faces, closely adherent to those of 

 the First Radials on either side : a, external fiice. 

 Fig. 2. Second Radial. 



Fig. 3. Third or Axillary Radial ; dl, vertical ridge dividing the two articular faces. 

 Fig. 4. First Brachial. 

 Fig. 5. Second Brachial. 



Fig. 6. Third Brachial, united in o, d, and E with the Fourth. 

 Fig. 7. Fourth Brachial. 

 Fig. 8. Fifth Brachial. 



MDCCCLXVI. 5 J 



