EXPLANATION OF PLATES OE PEOEESSOE HALL'S REPORT. 



PLATE I. 



Fig. 1.— PTKINA PARRTI. 



Fig. 1 a. Upper side. 

 1 b. Lower side. 

 1 c. Posterior side. 



1 d. Enlargement of the surface showing the larger and smaller granulations, ambu- 



lacral pores, etc. 



Fio. 2.— TOXASTEK TEXANUS. 



Fig. 2 a. View of the base. 



2 b. View of the summit. 



2 c. Posterior view. 



Fig. 3.— CYPHOSOMA TEXANUM. 

 Fig. 3 a. Profile view. 



3 b. View of base. 



3 c. Enlargement of ambulacral and interambulacral spaces, (figures from Roemer.) 



FiQ. 4.— HOLECTTPUS PLANATUS. 

 Fig. 4 a. Profile view. 



4 b. Summit. 

 4 c. Base. 



4 d. Enlargement of the summit of the test. 



4 e. Enlargement of the ambulacral and interambulacral spaces. 



4/, g. Base of attachment of spine enlarged. 



PLATE II. 



Fio. 1.— CAPUINA OCCIDENTALIS. 



Fig. 1 a, b. Upper and lower sides. 



1 c. Transverse section. 



Fio. 2.— CAPRINA PLANATA. 



Fig. 2 a. A fragment one third the linear dimensions. 



2 b. Enlargement showing structure. 



Fig. 3.— TDKBINOIJA TEXAN A 



Fig. 3 a. Specimen natural size. 



3 b. Enlargement of the lamellae. 



