566 BULLETIN 106, UNITED STATES NATIONAL MUSEUM. 



ADEONELLOPSIS QUISENBERRYAE, new species. 

 Plate 15, figs. 20-26. 



Description. The zoarium is free, bilamellar, formed of widened fronds 

 branching dichotomously ; the two lamellae are placed back to back and are sep- 

 arable. The zooecia are elongated, distinct, separated by a furrow, surrounded by 

 an especial line of numerous parietal areolae. The total area contains the aperture, 

 the avicularium, and the cribriform area; the apertura in the interior is semilunar 

 and transverse; the avicularium is very large, triangular, pointed and placed 

 obliquely, its point touching one of the lateral walls ; the cribriform area, little visible 

 exteriorly, bears from five to seven small stellate pores on the interioi. A salient, 

 i-lliptical, adventitious avicularium is located at the base of each zooecium. 



Lz= 0.52-0.56 mm. 



Measurements. Zooecia 



la 0.30-0.36 mm. 



and 0.20 mm. (in the interior) 

 Length of the total area=0.16-0.30 mm. 

 Length of the avicularium=0.20 mm. 



Variations. On the young zooecia the cribriform area is small, exterior and 

 externally entirely uniporous (fig. 21). The old specimens have a total area; the 

 avicularium and the aperture are surrounded by a thick pleurocystal covering 

 (figs. 22, 23, 25). This latter is so active on the undulating lamellae that the 

 exterior zooecial measurements are larger than the interior measurements. 



The zooecial walls are very thick; they are striated and show clearly the 

 deposit of the pleurocyst, which is formed by the addition of successive layers on 

 the exterior (fig. 24). 



The basal zooecia (fig. 23) are covered with a calcareous deposit and lose their 

 polypide. The parietal areolae and the avicularium alone persist. 



Affinities. This species is characterized by its avicularium, which is so oblique 

 that its point touches one of the parietal walls of the total area. In Adeonellopsis 

 magniporosa and Adeonellopsis coscinophora Keuss, 1847, the avicularium is 

 straighter and in the total area never touches the walls. 



It accompanies Adeonellopsis transversa in the same localities and in which 

 the avicularium is also very oblique; it differs from it in its larger dimensions and 

 in its cribriform area uniporous exteriorly and multiporous interiorly. 



We dedicate this species to Adelaide C. Quisenberry in appreciation of the in- 

 terest she has taken in this work and of her help in its preparation. 



Occurrence. Claibornian (Gosport sand) : One mile southwest of Eockville, 

 Clarke County, Alabama (rare) : Gopher Hill, Tombigbee River, Alabama (rare). 



Lower Jacksonian (Moodys marl) : Jackson, Mississippi (rare). 



Cotypes.C&i. Nos. 63856. 63857, U.S.N.M. 



ADEONELLOPSIS TRANSVERSA, new species. 



Plate 15, figs. 11-19. 



Description. The zoarium is free and bilamellar, the two lamellae being sep- 

 arable. The ordinary zooecia are elongated, little distinct, separated by a furrow. 



