s 



DESCRIPTIONS OF SPECIES, 189 



It seems to be cnly a large overgrown specimen of Eudopaclnjs maclurii var. 

 triangulare. 



The following are a few notes on the finer structure of E. maclurii : 

 The structure of the wall is in all jjartieulars identical with that of 

 Eupsammia elaborata. The margins of the larger septa are entire; those of 

 higher (younger) cycles are dentate in their lower portions. The upper 

 portions of the margins of these septa are entire or obscurely dentate. The 

 septal faces are minutely striate, with granulations along the courses of the 

 striae. The septal trabeculoe are fine ; have a line of divergence at the inner 

 edge of the spongy perforate zone. Interior to the line of divergence the 

 trabeculse pass upward and inward and are usually directly continuous 

 across all gi-owth segments until they reach the septal margin. On tlie 

 outside of the line of divergence the trabeculpe seem first to pass upward 

 and outward for a short distance, and then to bend into a horizontal position. 

 Each septal perforation is due to the discontinuity of one or two trabeculje. 

 In the outer perforate and spongy zone synapticulse are very abundant. 

 PI. XXI, fig. 16, shows an enlarged view of the surface of a septum, the 

 outer coating peeled off. The septal structure, etc.. of Endopachys is iden- 

 tical with that of Rhectopsammia. 



Endopachys lonsdalei sp. nov. 

 PI. XXII, figs. 10 and 10a. 



Shape subcuneiform, ventricose, base gently rounded, margins not much 

 compressed, subparallel to each other. Looked at with the edge toward 

 one, the corallum slopes gradually from the calicular margin to the base. 

 The lateral tubercles are not prominent. There are in the upper portion 

 of the corallum distinct, fine, granular costaj corresponding to all the cycles 

 of septa; those of the first and second cycles slightly larger. On the 

 basal portion of the corallum these costae disappear, and the surface is 

 covered with granules. The wall is thick and vesiculate. The sejital 

 aiTangement is the same as in E. maclurii. Columella vesiculate. Greater 

 diameter of calice, 15.5 mm.; lesser diameter of calice, 12.5 mm.; height of 

 corallum, 13.5 mm. 



Localities. — Mouroe County and Cotfbeville, Alabama; Newton, Missis- 

 sippi; 4 J miles east of Newton, Mississippi; Wautubbee Hills, Mississippi 

 (apparently young of this species). 



