64 F. A. SMITT, 



Hab.: Coloniam crustaceam Coralio insidentem e prof. 13 orgyarum sustulit 



POURTALES. 



The typical form of the Lepralia edax, as in the Crag Polyzoa, it was first described 

 by Busk, will be distinguished from the two other forms, here to be described, by its mari- 

 ner of raising the front wall of the zooecia into a median umbo, just proximally of the 

 zooecial aperture. Furthermore, it seems to want the avicularia as well as the ocecia, what 

 character, however, in systematical respect, can be of no use. In the Quart. Journ. Micr. 

 Se., cited below in the preceding page, in describing the Devonshire specimen, Busk 

 presents another variety of the European form, with the zooacial wall punetured, rough 

 (roughly verrucose in the figure) and with the form of the zooecial aperture, (in the 

 one of the figured zooecia) more approaching to the preceding Lepralia cleidostoma. 

 With this zooecial constitution, off Elbow reef a little fragment was taken by Pourta- 

 les. It is about 4 mm. high, 2 mm. broad, a little compressed, pointed, of pumicose 

 consistence. Besides the zooecial apertures of the typical form, here, also, I find some 

 of them almost entirely agreeing with the last-named species. Thus, the breadth of 

 the distal part of one zooecial aperture can be measured to be about 0,06 mm., while the 

 same measurement of its proximal part gives not more than 0,030 mm. As a third 

 European variety of this species I regard the Lepralia lata 1 ), which, in comparison 

 with the other forms, in the plainness of its zooecia, arranged in only a single layer, 

 retains the escharine constitution unaltered. That same peculiarity, although not in 

 the same degree, among the Floridan forms, distinguishes the Lepralia janthina, which 

 in its size, also, almost agrees with the Lepralia lata, its zooecial aperture having a 

 breadth of about 0,u mm., and, in the growing edge of the colony (hg. 224) it differs 

 from that form, principally, by the more ovate shape of the zooecia, with a more con- 

 vex front-side, in the middle of which they are provided with a lateral avicularium, 

 with a triangulär mandible, pointing distally, towards the zooecial aperture. The mar- 

 gin of this aperture is sharply defined, a little raised, and, usually of a little whitish 

 tint, in contrast with the black-bluish colour of the zooecial wall. In the middle of 

 the roundish colony, the zooecia, in the celleporine manner, are raised (hg. 225) and 

 heaped together, irregularly. The avicularium, then, as very common among the Celle- 

 porines, will be raised into a freely ascending process. 



This change into the celleporine constitution, the Lepralia calcarea almost enti- 

 rely has undergone. It was found, by Pourtales, growing in raised stems of a pu- 

 micose consistence. Once (fig. 221) a Serpula, I think, had fixed itself upon such a 

 colony, where, at last, is a was enveloped by the overgrowing Bryozoon, and its calca- 

 reous shell, in the well-known manner, was eaten away. Thus, the inner surface of 

 the Serpulan tube, longitudinally striated and densely prickled by warts and impres- 

 sions, now »is formed by the backs of the bryozoan cells disposed in parallel rows,» 

 »much as they are on the concave surface of some Lunulites». 



') Busk, Quart. Journ. Micr. So., vol. IV p. 309, Zoophytol. tab. X, figg. 1 et 2; Manzoni, Bryoz. Plioc. 

 Ital. Sitzb. k. Akad. Wiss. Wien, vol. LIX (1869), p. 4 (sep.), tab. 1 fig. 6. 



