FORAMINIFER A— HERON-ALLEN AND EARLAND. 81 



This variety is based on two specimens only, one eacli from Stations 45 

 and 55. They are both sessile organisms, but detached from the host and ex- 

 hibiting a labyrinthic structure of the base, as in D. limosa, var. humilis. Both 

 are fragmentary, inasmuch as they terminate abruptly at the trunk stage ; but 

 one of the specimens (Fig. 19) exhibits a broadening at the point of fracture, 

 which probably indicates a branching of the trunk. 



In their construction and appearance they appear to be more clearly allied 

 to the New Zealand form, D. arborescens, than to the Antarctic D. limosa, var. 

 humilis. 



Dimensions of the two specimens are as follows : — 



Basal pad, '70 and I'Omm. diameter. Height of trunk to point of fractm'e, 

 I'O and 2- 10 mm.; breadth of trunk, -30 and ■40 mm. 



76. Dendronina limosa, sp. nov. PI. II, figs. 1-6. 



Test sessile or free, consisting of a swollen basal chamber with entire or 

 labyrinthic cavity. From the basal chamber arise one or more tubular extensions, 

 unseptate and of gradually diminishing diameter. The tubes are usually simple, 

 but a single instance of furcation has been observed. Aperture terminal and simple, 

 formed by the constriction of the terminal end of the tube. Test constructed 

 of fine mud and sand-grains with little cement, surface rather rough, colour 

 yellowish grey. Walls of basal chamber and tube rather thin, much thinner than 

 in D. arborescens, with the result that the bore of the tube is considerably larger 

 than in that^ species. No spicules are employed in the construction of the test, 

 and the organism is in consequence very fragile, though possibly more or less 

 flexible in the living state. In some apparently free-growing specimens the basal 

 chamber is surrounded with a cheval-de-frise of projecting spicules (Figs. 2, 3). 

 It is possible that these may have been incorporated for anchoring purposes, but it 

 is more probable that the specimens were loosely attached to a living sponge. 



Confined to the New Zealand area, where it occurs in company with D. 

 arborescens. It may be regarded as a primitive type of the genus. Owing to its 

 extreme fragility the specimens are in a less perfect condition than the types 

 of that species, but it is probably equally abundant under suitable conditions. 



Size : — The basal chamber in both free and sessile specimens ranges up to 

 1-20 mm. Maximum height unknown, but probably does not exceed 2 or 3 mm. 

 Thickness of wall varies from •12 mm. at the base to -OSnnn. at the extremities 

 of the tubes, which average -30 mm. in diameter. 



77. Dendronina limosa, var. humilis, nov. PI. II. figs. 7-9. 



Station 26. 



Test sessile, composed of fine sand-grains and a little cement, but without 

 incorporated sponge-spicules. Consisting of a basal portion with labyrinthic 



VOL. VI. M 



