REPORT ON THE POLYZOA. 37 



The distinction between this form and Vesiculana spinosa is too obvious to require 

 remark. '' But there" is a second species, which occurred in the " Eattlesnake " collection, and 

 was procured between Cumberland Island and Point Slade, which appears to be very 

 closely allied, and I have, therefore, thought it might be useful to give a description 

 of it, thought not strictly belonging to the Challenger Expedition. 



(2) Vesiculana trichotoma (PI. VIII. fig. 4). 



Character: — Zoarium of irregular straggling growth, main stems or primary branches 

 about 0"2 in diameter, and usually barren, thick-walled. Primary branching, trichotomous, 

 secondary usually furcate. Secondary and tertiary branches much slenderer, thin-waUed. 

 The internodes support eight to ten zocEcia, disposed alternately in a double series on 

 only one side of the branch ; in the youngest segments there is only a single row. 

 Zooecia very readily detached, ovoid, and about 0"4 x 0"2 mm. The surface is smooth and 

 the neck short. 



Habitat. — Bass Strait, between Cumberland Island and Point Slade, Voyage of 

 H.M.S. •" Rattlesnake."^ 



A peculiarity at once distinctive of this form is the trichotomous division of the 

 primary branches ; the great difference in diameter of the branches is also characteristic, 

 as distinguishing it from the preceding, with which it agrees in the alternate arrange- 

 ment of the zooecia on the internodes. 



2. Farrella, Ehrenburg. 



Farrella, Ehrenb., Johnst., Busk, Engl. Cyclop.; Hincks, Brit. Mar. Polyz., p. 528, &c. 

 Lagenella, Farre, W. Thomson, Hassall. 

 Laguncula, Van Benedeu. 



Character. — Zoarium stolonate, free, or creeping and adherent ; branching irregularly 

 or at definite intervals. Zooecia cylindrical or subventricose below, pedunculate. Orifice, 

 when the neck (goulot) is retracted, bilabiate or quadrangular. Neck long, tapering, 

 with or without a crown of setae.'' (No gizzard). 



(l) Farrella atlantica, n. sp. (PI. VII. fig. 3). 



Character. — Zoarium stolonate, filamentous, jointed at regular intervals, free or 

 creeping and aduate. Stolon 0-02 to 0'04 mm. in diameter, throwing out three or four 

 short branches or zooecia close below each joint at regular intervals. Zooecia with the 



1 This species does not occur in the Challenger collection. 



• It does not seem to have hitherto been remarked that the genus Laguncula (V. B.), as exemplified in Laguneula 

 repaut and Laguncula elongala, has no sets. 



