516 



BULLETIN 106, UNITED STATES NATIONAL MUSEUM. 

 Genus HASWELLIA Busk, 1884. 



1S84. Ilasioellia BUSK, Report on the Polyzoa collected by H. M. S. Challenger, pt. 1, p. 171. 



The apertura has its pi'oximal border notched by a very wide rimule not sep- 

 arated from the anter. The frontal is a very thick tremocyst. The spiramen is a 

 small salient tube. The zoariuin is cylindrical. 



Genotype. HasweUia (Myriozoum) austraUensis Haswell, 1880. 



Range. Jacksonian Recent. 



sp 



M 



J <" K 



FIG. 150. Geuus HasweUia Busk, 18S4. 



A-K. HasweUia austraUensis Haswell, 1889. A. Zooecia, X 25. B, C, D, E. Successive 



aspects of the visible orifice, X 50, showing development of the peristomie. F. Zoarium natural 



size. (A-F after Busk, 1884.) G. Operculum, X 85. (After Waters, 1881.) H. Operculum, 



C 75. (After Levinseu, 1009.) I. Transverse section. (After Busk, 1SS4.) J. Longitudinal 



section, X 25. (After Waters, 1909.) K. Longitudinal section, X 17. (After Levinsen, 1909.) 



ap, apertura ; op, operculum closing the apertura ; ov, ovicell ; pe, peristome ; pi, peristomie : 



pis, peristomice; sp, spiramen; tr, frontal tremocyst. 



