BRYOZOA 83 



are distinguishable, and there are, hère and there, small semicircular avicularia, also fenestral 

 avicularia, with thin spatulate mandibles, and a few similar ones near the border of the 

 fenestrae. Thèse appear to be the elliptical avicularia enlarged. There are i5 tentacles. 



The above description is of a spécimen from N° 322, and there is also one from N°428 

 (dry) which has larger meshes about 3.6 mm X 2 mm quite corresponding with Busk's figure of 

 R. gigantea, but it is smooth and has but few of the semicircular avicularia on the anterior 

 surface, and no labial avicularia. It would be interesting to compare a larger séries of 

 R. gigantea B. and R. laevigata sp. nov. As to spécimen N° 428 there is considérable uncertainty, 

 and unfortunately the opercula are wanting. 



Habitat. — Exp. Antarct. Belge. 



N os 3og, 320 (1 pièce each), Tangles II. Lat. 71 14' S.- Long. 8g°i4' W.; 460 met.; -)-o.3 C. 



N° 322 (1 pièce), Tangles III. Lat. 71 24' S.- Long. 8g° 12' W., 460 met.; -f o.3 C. 



N° 428 (1 pièce), Tangles VI. Lat. 71 19' S.- Long. 87° 37' W., 436 met.; — 0.2 C. 



Retepora lepralioides sp. nov. 



(PL VI, figs. 3a-d) 



Judging from the largest pièce, measuring about 3o mm X about io mm which is not very 

 much curved, the zoarium evidently attains to a considérable size. The fenestrae are large 

 and usuallv rather wider than the branches, the average length of the fenestrae being about 3 mm . 



The zoœcia are elongate, smooth, with small elliptical avicularia on the front, and to 

 a few zoœcia there are large raised beaked avicularia directed forwards, the mandibles are 

 triangular, elongate at the end. There are also large fenestral avicularia directed towards 

 the interior of the fenestrae, visible both from the back and the front, and with similar man- 

 dibles to those of the large avicularia on the zoœcia. The secondary aperture is but little 

 above the oral aperture, and has a broad sinus, formed by the sides of the peristome being 

 raised. The oral aperture is nearly straight below, with the sides also nearly straight, and is 

 longer than broad ; the two oral spines are only seen in some zoœcia. 



The ovicell is globular, much raised, fairly open in front, with in some cases a médian 

 fissure. The anterior zoœcial divisions extend to the front of the ovicells, and in some ovicells, 

 only thèse divisional lines are seen, while in others the fissure can be distinguished. 



Dorsal surface divided by vibices and with numerous small elliptical avicularia. 



There are r.3-14 tentacles and long suboral glands, as well as avicularian glands; there 

 are a few ovaria and testes with spermatozoa. 



This has many points of similarity with R. antarctica sp. nov., but the zoœcia are longer, 

 and there are a number of large avicularia directed forwards, whereas in R. antarctica, the few 

 large avicularia are turned sideways, and may be replaced by small avicularia within the 

 aperture. The raised globular ovicell is another distinguishing character, but most important 

 of ail, is the différence in the shape of the oral aperture and the operculum. 



Habitat. — Exp. Antarct. Belge. 



N° 742, Tangles IX. Lat. 70 20' S.- Long. 83° 23' W.; 469 met.; +0.8 C. 



2 pièces in alcohol but the smaller is probably broken off from the larger. 



N° io32, do do do only fragments. 



