“Hoplakithara Dendyi*.
Sponge in form of a small cushion, attached by a narrow base. Surface smooth to the naked eye. Colour pale brown in spirit. Consistence, hard externally, soft within. Flagellated chambers 32.5µ in diameter, spheroidal, eurypylous.
Skeleton with protective armour formed by gigantic spheroidal heads of exotyles, the exotyles being arranged as radiating bundles in form of inverted cones, with the apices a little below the cortex; with scattered strongyles.
Spicules.—Megascleres: exotyles, with the heads a little inclined to the long axis of the spicule, the proximal end (in the interior of the sponge) rounded, the distal end swollen into large spherical heads, with short cylindrical spines covering the distal three-fourths of the head. Total length 358µ, the shaft enlarging in diameter from 6.5µ at the proximal end to 16µ just below the head. Head 55µ in diameter; cylindrical denticles 1.76 to 3.52µ in height, with finely denticulate edge, and with cup-like depression at the summit.
Strongyles straight, fusiform, smooth, 467.5µ long, 9.75µ in diameter at centre, 6.5µ in diameter at ends.
Microscleres: placocheles, fimbriated, 84.5µ long, 29.25µ broad; length of tooth 37.75µ
Sigmata very small, slender, C-shaped, 8.8µ long, 5.28µ broad, .9 µ thick.
The minute spheroidal or cushion-shaped specimen was 2.2 mm. in height and 3 mm. in horizontal diameter; it was growing on the side of an Alcyonarian creeping over a branched Cellepora. No pores or oscules were discernible. The under surface, which was narrowed to the point of attachment, was paler in colour than the upper.
The new genus is closely related to the Mycaline genera Rhaphidotheca and Guitarra, to the former by its exotyles, and to the latter by its fimbriated placocheles.
The distal knobs of the exotyles of R. Marshall-Hallii, Kent, 49 µ in diameter, are smooth and spherical, and those of R. rhopalophora, Schmidt (R. affinis, Carter), are 104 µ long and 30µ broad, and club-shaped. Lundbeck regards these two species as probably identical, and certainly the differences are slight.
Locality. Winter Quarters, 130 fath.
* Named in honour of Professor Dr. A. Dendy.”
(Kirkpatrick, 1907: 286)
