Polyzoa of the Adriatic. 305 



occasionally within it ; a veiy long subspatiilate appendage, 

 originating at the side of the orifice and stretching down two 

 thirds or more of the cell, mandible of very delicate material, 

 slightly spatulate ; commonly on the opposite side of the cell, 

 a very slender elongate avicularium of much smaller size, 

 with an attenuated mandible ; often a small form with very 

 slender pointed mandible at the side of the orifice near the 

 top, replaced sometimes by a pair (with triangular mandible) 

 placed one on each side and directed inwards. Oeecium sub- 

 orbicular, much depressed, thickly covered with small punc- 

 tures, and with a smooth line round the base. 



Professor Smitt has described this form from the Floridan 

 seas, ranking it under his Eschar ella Jacotini {=Snuttia 

 trispinosa, Johnston) as a variety. I have taken the same 

 view of it * ; but I confess that an examination of specimens 

 from the Adriatic, where it seems to be common, has some- 

 what shaken my previous opinion. S. trispinosa is undoubt- 

 edly a very variable species, but the present form seems to be 

 differentiated from the type by characters of some significance. 

 As it occurs in the British seas it is furnished with only two 

 kinds of avicularium — one small and oval in shape, which is 

 usually placed at the side of the orifice, though occasionally 

 distributed irregularly and profusely over the zoarium, and 

 the second larger, with an elongate triangular mandible vari- 

 ously situated. The var. spathulata is remarkable for the 

 diversity of structure which the avicularian appendage exhi- 

 bits J no less than two or three very distinct modifications 

 occur, of which the most marked is the large spatulate form. 

 This is present in great numbers and very materially affects 

 the appearance of the species. The small avicularium, with 

 very finely pointed man lible below or within the sinus, is also 

 a notable character (PI. IX. figs. 3, 3 a). The orifice in the 

 specimens from the Adriatic differs in some degree from that of 

 our British form, so far as I have observed it, being com- 

 monly more elongate. The ooecium is very much depressed, 

 almost level with the general surface ; the small group of 

 somewhat pyriform openings in the centre of the front wall, 

 which is so characteristic of the British form, is wanting, and 

 the surface is thickly covered with minute punctures. It 

 may be added that the yellow colouring of the crust by which 

 the species can usually be distinguished at once, and which is 

 not evanescent, is absent. 



On the whole, it will probably be safer to refer the present 

 form to 8. trispinosa, of which it must be accounted a very 



* Ann. & Mag. Nat. Hist, for October, 1884, p. 2S2, pi. ix. fi"-. 4. 



