LOXOSOMA SINGULARS. 573 



but not exclusively, as " commensals " with various spe- 

 cies of Annelida. They have also occurred on Sponge, 

 and on other Polyzoa (e. g. Bugula and Zoobotryon) . 



LoxosoMA siNGULARE, Kefcrstcin. 

 Plate LXXXI. figs. 7, 8. 



LoxosoMA SINGULARE, KefersteiTi, Zeitschrift f. wiss. Zool. xii. (1862) 13, 

 pi. xi. fig. 29 : Claparede, Eeob. iib. An. u. etitw. wirbell. 

 Thiere an d. Kuste v. Normandie, 135, pi. ii. figs. 6-10 : 

 Barrois, Embryol. d. Bryoz. 9 & 10, pi. i. & pi. xvi. fig. 6. 



Body oval; tentacles 10; peduncle short (about half the 

 length of the body) and stout, wrinkled transversely, 

 terminating below in a discoid expansion, by which the 

 polypide is attached ; no pedal gland in the adult; 1-3 

 buds on each side. 



In the specimens examined by Keferstein only a single 

 bud seems to have been developed on each side ; but in 

 Shetland examples, which I owe to Dr. M'Intosh, as many 

 as three are sometimes present on a side. 



The short peduncle, narrowing slightly downwards, 

 with its disk-like foot, is a character which separates this 

 species from all its congeners. 



Habitat. On Annelids. 



Locality. Shetland, on Latin o nice Jilico mis (Dr. JNI'In- 

 tosh) . 



Geographical Distribution. St. Vaast-la-Hougue, 

 abundant, on Capitella rubicunda (Keferstein) : ibid, on 

 the ventral surface of Aphrodite, in company with Pedi- 

 cellina gracilis &c. (Barrois) . 



