ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 259 



New Avian Cestode. * --H. A. Baylis gives an account of the 

 structure of Tetrabothrius Strang ulatus sp. n. from an albatross (Diomedea 

 irrorata). It is very small — a complete, specimen probably being about 

 60 mm. long, with about 250 proglottides. The maximum width 

 observed was about 0'77 mm. A marked feature is the "strangled" 

 appearance due to a very marked demarcation of the head from the neck. 

 The small number of testes (eight to nine) is also characteristic. In 

 its internal organs it approaches closely to Tetrabothrius heteroditus 

 Diesino-. 



Incertae Sedis. 



Enigmatical Animal.f. — M. Caullery returns to the peculiar animal 

 which he has made the type of a new family, Siboglidas, of unknown 

 affinities. The creature lives in an annulated tube, and is somewhat 

 suggestive of the more delicate Cha?topterids, like Phyllochsetopterus, but 

 the bad state of preservation made definite statements difficult. 



Echinoderma. 



Abnormal Gills of Porania pulvillus.J — James F. Gemmill 

 describes a specimen with infra-marginal actinal as well as abactinal 

 gills. Starfishes with well-developed marginal plates (Phanerozonia) 

 have their papula? or gills limited to that part of the abactinal surface 

 which is bounded by the supero-marginal plates. The case described 

 shows that this does not always hold. Moreover, Gemmill has recently 

 shown that the larval history of the phanerozonate Porania, resembles 

 in its essentials that of the typically cryptonate Aster ias, both species 

 having a feeding bipinnarial larva which changes into a brachiolaria 

 and becomes attached at metamorphosis. " Probably the occasional 

 presence of infra-marginal gills in Porania is not due directly to 

 atavistic or ancestral causes, but ! is a parallel manifestation, in an 

 individual belonging to a particular asterid Family, of a tendency or 

 potency which has been fully realized in the various members of 

 numerous other Families." 



Development of Some Japanese Echinoderms.§— Th. Mortensen 

 finds that the larva? within an order or family have certain characters 

 in common. The larva of Strongylocentrotus pulcherrimus has for 

 body-skeleton long club-shaped rods and an elongated posterior end of 

 the body, as is the case in the larva? of S. droebachiensis and in true 

 Echinus species. This leads Mortensen to think that Strongylocentrotus 

 is nearly related to the Echinidae sens a, stricto and not to the Toxop- 

 neustidas. In the latter the larvae have quite another shape, namely a 



* Proc. Zool. Soc, 1914, pp. 407-13 (4 figs.). 



t Bull. Soc. Zool. France, xxxix. (1915) pp. 350-3 (8 figs.). 



t Proc. Zool. Soc, 1915, pp. 21-3 (1 fig.). 



§ Annot. Zool. Japon, viii. (1914) pp. 543-52 (2 figs.). 



