LOXOSOMID^E. 571 



and Tynemouth, common (Alder) : Shetland, rare (A. 

 M. N.) 



GEOGRAPHICAL DISTRIBUTION. Norway (Sars) : Spitz- 

 bergen, 30 fathoms (Malmgren, fide Smitt) : White Sea, 

 on Lafoea dumosa (Mereschkowsky) : Roscoff (Joliet). 



Family II. Loxosomidse. 



POLYPIDES borne on a contractile peduncle, solitary, always 

 furnished in the young state with a pedal gland ; gemma 

 produced on the body of the polypide. 



THE Loxosomida agree in all essential points with the 

 Pedicellinida ; but they are solitary animals, and this 

 character is accompanied by certain variations in the 

 common plan of structure. Their leading family pecu- 

 liarities are all determined by this point in their history. 

 The foot-gland for attachment, which is always present in 

 the young, though frequently aborted in the adult, is 

 rendered necessary by the absence of any adherent stolon. 

 The mode of gemmation is dependent on the same cir- 

 cumstance*. 



Curious tactile organs, placed one on each side of the 

 body, and consisting of contractile papillae supporting a 

 number of delicate setae, have been noticed in some spe- 

 cies, and are probably always present. 



* Alder records two cases in which he had obserred the production of 

 buds in Pedicellina from the polypide. " In one the young arose from the 

 body of the animal, and at right angles to it ; in the other from the stem a 

 little below the body" (Suppl. to Northumb. Cat. p. 22, sep.). Barrois 

 (in his ' Embryologie des Bryozoaires,' pi. ii. fig. 15) represents a discoid 

 mass at the base of the peduncle in the primary polypide of Pedicellina, 

 which, he conjectures, may be the rudiment of a pedal gland. We may 

 hare here memorials of the solitary ancestry of the present colonial forms. 



