a General History of the Marine Polyzoa. 133 
gera, which are placed nearer the top of the cell than that of 
D. distans; they also differ in form (Plate V. fig. 6 com- 
pared with fig. 7), and are especially remarkable for the 
length of the free portion of the beak. ‘The mandible becomes 
much attenuated towards the apex. 
Diachoris intermedia, n. sp. 
(PI Via tie 83) 
Zoecia small, elongate, open in front, the aperture narrow- 
ing slightly downwards, decumbent, three (or two) denticles 
at the top of the cell, and a small spinous process at each side 
in a line with the lower margin of the oral valve; on each 
side a small aviculariwm, placed at a very short distance 
below the top; beak short and slightly bent. Dorsal surface 
perfectly smooth and destitute of spines ; each cell connected 
by short tubular processes with four others, two terminal and 
two lateral, the latter originating at opposite points on the 
side-wall a little above the middle. Occcum (?). 
Loc. Tasmania, on an alga (Miss Gatty). 
This is a minute species, and is interesting as in some mea- 
sure a transition form between the genera Déachoris and 
Beania. ‘The simple plan of the zoarium allies it to the latter 
genus, while in the decumbent cell armed with avicularia it 
resembles the former. ‘The species described by Mr. Ridley 
from the Straits of Magellan as Chaunosia fragilis* ap- 
proaches still more nearly to Beania; its polypide, however, 
is said to be furnished with a gizzard, and it may possibly be 
entitled to generic rank. Its affinities are much more with 
Beania than Diachoris. 
Diachoris hiriissima, Heller, form robusta. 
(EEVesteso se oias) 
Zoecia large, suberect, boat-shaped, expanded below, and 
narrowing off rather abruptly towards the oral extremity into 
a kind of neck, entirely open in front; three very large acu- 
minate spines at the top, and four tall stout ones immediately 
below them placed two at each side, flanking the oral valve ; 
below these again four or five tall spines, originating just out- 
side the margin, from the base of which spring as many slen- 
der spiules, which bend over the aperture ; at one side near 
the top an avicularium, subglobose, with a very small and 
slightly projecting beak and a broad mandible; connecting- 
tubes extremely short, sixinnumber. Dorsal surface smooth, 
* Proc. Zool. Soc. 1881, p. 45. 
