BRITISH PAL^OGENE BETOZOA. 255 



M. chilopom (Reuss) i, but the general form of the zooecia and the structure of the 

 inucro are quite distinct in the two species. 



Mr. A. Bell's collection of Fareham Bryozoa having recently passed into the posses- 

 sion of the British Museum, I am able to identify with this species the specimen 

 referred to by Vine as Porella concinna. 



Mr. Waters, in his ' Revision of the North Italian Bryozoa,' does not quote Mucro- 

 nella from the Eocene deposits of that country. The genus occurs in the Austrian 

 Leithakalk (Helvetian), as at least two species, M. serrulata (Reuss) ^ and M. tenera 

 (Reuss) ^, seem referable to it. 



Mr. Waters [No. ii, pp. 14, 15] has shown that under the name " mucro " several 

 distinct structures have been confused together, and he has proposed the dismemberment 

 of Mucronella and the incorporation of most of its species in Smittia. The generic 

 value of variations in the secondary orifice and its peris tomial tube certainly appears 

 very doubtful, but there does seem sufficient difference between this group of species of 

 Mucronella and normal i^HwYiJ/ff? to justify the limitation and retention of Mr. Hincks's 

 too comprehensive genus. 



Genus Smittia, Hincks, 1880. 

 Diagnosis. Hincks, No. i, p. 340. 



Species 1. Smittia tubularis *, n. sp. 



Diaf/nosis. Zoarium erect ; narrow cylindrical or shoot-like branches ; branching 

 dichotomous. 



Zooecia arranged alternately. Shape pyriform ; ovate or elongate-ovate. Front wall 

 tumid; surface granular. Secondary orifice orbicular or a distinct spout-like depression 

 often shown on lower margin. Peristome thin. A row of large areolse occurs around 

 the margin. 



Ooecia small, flattened, the lower side covered by the upper margin of the secondary 

 orifice. 



Avicularia large, lateral, on a prominent tubercle obliquely below the orifice. 



Bistribution. London Clay, White Conduit House. 



Type. Brit. Mus. No. 49744. Edwards Coll. 



Figures. PL XXXII. fig. 1 a. Zoarium, nat. size. Fig. 1 h. Several zooecia, enlarged. 

 Fig. 1 c. Basal zooecia. 



^ Cellepora cJiilopora, Eeuss, No. i, p. 91, pi. xi. fig. 4, and No. 14, p. 168, pi. iv. fig. 1. 

 ^ Oellepora serrulata, Eeuss, No. i, p. 85, pi. x. fig. 12; and Lepralia serrulata, Eeuss, No. 14, p. 167, pi. ii, 

 figs. 2, 3 (? pi. iv. fig. 4). 



" Lepralia tenera, Eeuss, No. 14, p. 167, pi. ii- fig. 4, pi. iii. fig. 11. 

 * Eeferring to the subtubular orifice. 



