REPORT ON THE POLYZOA. 
173 
nature. It has no communication with the body of the cell, as in that genus, nor has it 
the same tubular character, and its original mode of formation is apparently quite different. 
It belongs to what might be termed the simply suboral pores, whose function like that of 
the other special pores at present is altogether conjectural, but may be anal. 
In the older or lower portions of the growth the peristomal tube becomes shorter and 
thicker and for the most part so mutilated as to present no trace of the trifid division of 
the anterior lip, the middle tooth of which however remains more or less distinct and is 
sometimes produced into a downwardly curved sort of beak. 
(2) Haswellia auriculata, n. sp. (PI. XXIV. fig. 10). 
Character.- — Zoarium about 0 "‘75 to l" high, composed of short forked branches. 
Zocecia irregularly verticillate, about six in each whorl and usually in pairs ; when young 
ovate slightly convex, when old completely immersed. A marginal row of distinct 
puncta round the border. Primary orifice horizontal, orbiculo-emarginate with a thin 
pointed process of the peristome on each side, supporting minute avicularia with an acute 
triangular mandible pointing upwards, the peristome afterwards becoming more or less 
tubular with a deep notch and sometimes a suboral pore in front. Ocecia numerous, with 
a circular area in front surrounded by a narrow raised fillet. 
Habitat. — Station 135c, off Nightingale Island, 110 to 150 fathoms, and (135a) oil’ 
Inaccessible Island, Tristan da Cunha, 75 to 90 fathoms, hard ground, shells, gravel. 
Station 142, lat. 35° 4' S., long 18° 37' E., 150 fathoms, green sand. 
It is with some hesitation that I conjoin this species with the preceding, but as it 
seems to present more points of resemblance with Haswellia australiensis than with any 
other form with which I am acquainted, it seems convenient to do so provisionally at 
any rate rather than give it a separate generic appellation. 
The younger zooecia are quite distinct, with a sub tubular orifice at first presenting a 
thin lamina on each side, which as they grow together more or less completely form an 
imperfectly tubular peristome, with a deep notch in front which sometimes eventually 
becomes a suboral pore, as in Haswellia australiensis, but which as in that species cannot 
he regarded as homologous with the median pore of Tessaradoma, &c. The row of mar- 
ginal puncta is a feature also in common with Tessaradoma. But the difference in the 
present species, m this respect, between the older and younger portions of the zoarium is 
very great ; also owing to the great thickening of the walls and the consequent deep im- 
mersion of the mouth, the lateral avicularia are deeply placed and may easily be over- 
looked. The ooecia in Haswellia auriculata are remarkable for their great number, almost 
all the cells in some specimens being crowned by one. In the younger unthickened 
parts these organs are subglobose and rather prominent, but they soon become more or 
