256 ME. AETHTTE W. WATEES ON 



consider one of the most important features of tlie genus. This 

 pore is frequently the opening of a long tube which runs down 

 the peristome close to the opercular opening. At one time I 

 thought that it sometimes opened on the zocecial side of the 

 operculum, but I have not been able to satisfy myself that 

 this is the case. The tube of this sublabial pore can be most 

 distinctly seen in Betepora Jissa (PL YII. figs. 21 and 22). In 

 Betepora Imperati, Busk, from Porto Praya, I am unable to 

 find it in calcined specimens in my possession ; whereas in 

 M. Solanderia, which is so closely related as to leave it doubtful 

 whether it might not be placed as a variety, the pore is distinctly 

 visible. In a specimen of B. cellulosa from the North Cape there 

 are very frequently (PI. YI. fig. 17) two such pores, one on each 

 side. 



The ovicells are usually raised and nearly always have a more 

 or less fissured opening. There is the plain narrow fissure of the 

 B. cellulosa-fissa group ; the wide fissure of the B.-Imperati 

 group ; and the irregular denticulate fissure of the B.~monilifera 

 group (see pi. iii. fig. 11 of my ' Challenger ' Supplementary 

 Report). In spite of considerable difference in the appearance 

 of the ovicells in the three groups they are seen to pass through 

 various gradations, showing in reality similarity of structure. 

 The B. elongata, Smitt, however, has an entire ovicell, which 

 when mature is either straight below or has a slight peak, as in 

 fig. 9, while in the younger ovicells the opening is thrown much 

 further back. The ovicells of B. tessellata, var. ccBspitosa, Busk 

 (PL VI. figs. 7, 8), show a similar difl^erence in young and mature 

 ovicells. 



The suhoral (/lands *, to which I have called attention, seem 

 to be well developed throughout the genus. Preparations made 

 where there was suitable material show them in all cases ; and I 

 have now seen them in B. avicularis, B. cellulosa, B. columnifera, 

 B. contortuplicata, B. Couchii, B. denticulata, B. elongata, B. 

 gigantea, B. jacksoniensis, B. mediterranea, B. tubulata, &c. 



It would seem that these glands occur quite generally through 

 the Schizothyriata of Grregory and possibly may give us assistance 

 in classification. I hope shortly to publish further observations 

 on these organs, which we may have to compare with the excretory 

 organs described by Cori in the Phylactolsemata. A form described 



* 'Challenger' Supp.Rep. vol.xxxi. p. 27; and "Observations on the Grland- 

 like Bodies in the Bryozoa," Journ. Linn. Soc., Zool. vol. xxiv. p. 272. 



