16 ME. A. "W. WATERS ON BETOZOA PEOM EAPALLO 



internode, and this upper portion does not seem to have 

 contained any polypide. It would thus seem that the upper 

 part of the stem may be cut off as a barren internode, carrying 

 a sessile avicularium identical in structure with those on the 

 mature zooecia. 



The erect stem does not start direct from the creeping tube, 

 but evidently there is a diaphragm, or rosette-plate, in the 

 extended stolon by which stem and stolon are in connexion. 



Beania magellanica, Busk. (PI. 2. figs. 11-14.) 



The small projections on the distal end of the zocecium, 

 described from my JSiaples specimens, ar^ also seen in those from 

 Eapallo. These Jullien did not find in the specimens from Cape 

 Yerd or from Tierra del Puego, but my observation has been 

 confirmed by others. 



The mandible of Seania magellanica and JB . hilaminata, Hincks, 

 has a double "columella." This I have figured (Journ. Eoy. 

 Micro. Soc. ser. 2, vol. v. pi. xiv. fig. 4). 



Ortman states that in the Japanese specimens the border of 

 the avicularium is dentate, but this is not the case with those 

 from the Mediterranean. 



As the large figure, given by Jullien, does not correctly show 

 the muscles of the avicularium, I have added figures showing 

 that besides the large adductors there is a semicircular row of" 

 short muscles, which no doubt contracts the integument behind 

 the mandible and thus helps in the slow opening of the beak- 

 The "cellular body" of the avicularium, as elsewhere mentioned, 

 occurs in a sheath, the equivalent of the sheath of the polypide. 



The " eggs " described by Jullien occur one on each side of. 

 the zocecium, in the same position as the ovarium, contain 

 refractive cells, and are similar in structure to what I term the 

 " median body " * in ScJiizoporella sanguinea. In my specimens 

 of Beania magellanica they are usually globular, but sometimes 

 become sausage-shaped. 



The zocBcia are often nearly filled by the testes which seem to 

 grow from the two sides, lower down than the ovarium. The 

 remains of the polypide become encysted, forming brown bodies. 

 The budding polypides originate from close to the connecting 

 tubes, in fact sometimes seem to be almost within them. 



* "Observations on Q-land-like Bodies in the Bryozoa," Linn. Soc. Journ., 

 Zool. Tol. xxiT., 1892. 



