190 AN^'ALS NEW YORK ACADEMY OF SCIENCES 



some i^peeimens than in others, and are very numerous. They are so fine and 

 ohscure that no satisfactory count can be made in the material available. 

 Mural pores apparently are small and regularly disposed. They seem to 

 occur in longitudinal rows near the angles of the cells. Tabulro vor.v closely 

 arranged and irregular. In some instances, they are oiie fifth to one eighth of a 

 cell diameter apart and seem to extend completel.v across in parallel plates. 

 In other instances, they are somewhat farther apart, oblique and vesicular. 

 Walls moderately thick. 



Menophyllum excavatum var. arkansanum var. nov. 



Corallum rather small, conical, showing much variation in the rapidity of 

 enlargement and in the amount of curvature. Exterior marked by the usuai 

 longitudinal striation. the striie being rather numeroiis and closely arranged 

 but not very strong. Calice deep. Septa at maturity about 28, fewer, of 

 course, in the earlier stages. Secondary septa present onl.v toward the upper 

 limit of the theca where they appear merely as slightly elevated ridges. Septa 

 and walls much thickened by stereoplasma, so that the interseptal loculi are 

 nearly closed. The three fossuljp are often clearly distinguishable, especially 

 in the more mature i)nrt of the corallum. Interseptal tis.sue practicall.v ab- 

 sent, rarely developed about the margins of the calicinal portion. 



Palaeacis carinata sp. nov. 



Corallum umch compressed, having flattened sides, narrowly rounded ends 

 and carinated lower portion. The height is less than the breadth, and the 

 ends are considerably lower than the middle. The cell-like cavities in the 

 specimens examined open onto the ui)per surface. The.v are few in number, 

 only four or five, and very shallow. The walls which separate them are low 

 and moderately thin. Fine and strong lirse cross the external surface. The 

 lirje are slightly narrower than the striip and begin near the point of attach- 

 ment as tubercles, which arrange themselves in rows and become connected 

 into continuous linear elevations. 



Fistulipora excellens var. harrisonensis var. nov. 



I'nder the present title. I am including thin 7A>aria characterized tangentially 

 by having rather large, closely arranged zonpcia with a distinct lunarium. 

 The zooecia average about .28 mm. in diameter, have a well-developed lunarium 

 and a conspicuously petaloid shape. They are sometimes in contact, but 

 usually are separated by narrow intervals of about one half their own diam- 

 eter occupied by single rows of cells. In or near macular areas, they stand 

 at about their own diameter apart and are separated b.v two rows of cells. 

 When closel.v arranged, 5 zooecia come in a distance of 2 mm. 



In vertical section, the zo(ecia are seen to have between them single columns 

 of subquadrate mesopores, while the diaphragms are rather abundant though 

 variable, standing at about a tube diameter apart. 



Fistulipora excellens var. williamsi var. nov. 



The zoaria occur as thin sheets 1 mm. or less in thickness and of no great 

 spread. The zorecia are small, about .21 mm. in diameter, with strongly 



