56 ARVID R. MOLANDER, ALCYONACEA. 
Gersemia clavata (DAN.), 1887. 
Diagnosis: The anthocodiae are numerous on each branch. The lower part of 
anthocodia with spicules. The branch bark with numerous spicules (basal spicules), 
which are short spindles, rods and rollers, up to 0.3 mm. in length, with uniformly 
distributed, strong thorns. (Pl. TI, figs. 2, 5.) 
1907, Eunephthya clavata, Gersemia crassa, Gersemia Danielseni, KUKENTHAL. 
The species recalls, in most respects, G. rubiformis. The low colony has in general 
an obvious, undivided trunk. 'The branches are short, swollen at the points, and do not 
cover the trunk. They are few in number, and their points are of equal size on the same 
specimen, varying from 4 to 8 mm. in transverse section. 'The branches bear the closely 
distributed anthocodiae. In consequence of its low, evident trunk, and rounded, small 
branch points with large anthocodia, and often with apparent, calyx, G. clavata pPossesses 
a very typical appearance. 
The anthocodiae are from 1 to 3 mm. in length and about half that in width. 
The armature is powerful. 'The lower part of the anthocodia, too, is provided with 
spicules. A calyx is often found. The spicules of the upper part of the anthocodia 
resemble those of G. rubiformis, but are more spindle-shaped and somewhat more thorned. 
They lie in double rows, but the strength of the armature varies rather much here. 
The spicules in the upper part of anthocodia are up to 0.420 mm. in length, in the branch 
bark 0.10—0.3 mm., in the trunk bark 0.10—0.15 mm. "The spicules in the calyx and at 
the points of the branches are very typical. They are large spindles and rods with the 
strong thorns distributed uniformly over the whole surface. MNpicules in the coenenchym 
between the coelenterons are rare. 
The canal system resembles that of the preceding species, but the walls between 
the coelenterons are narrower, and the endodermal cell-strings are limited in their 
extension and generally have the shape of narrow fillets. Direct connection exists, al- 
though not frequently. 
Among this species we also class Gersemia Damnielseni (STUDER) and Gersemia 
crassa (DAN.). 
Gersemia damntrelsenm. 
KÖUKENTHAL (1907) refers this species to Gersemia (sensu KUKENTHAL). 
STUDER (1901) refers it to his genus Paraspongodes. 
STUDER'S original specimen shows the following characteristics: The colony is 
about 30 mm. in height, and a few branches are distributed on the short trunk, which 
at the point divides into large branches. According to STUDER, the anthocodiae, which 
are packed on the terminal part of the thick, swelled branches, consist of a retractile 
part of about 2 mm. in length, and of a calyx 0.7 mm. high, with eight longitudinal rid- 
ges, terminating in small papillae. "This is perfectly correct, but it must be remarked 
that this calyx may be completely retractile. The branches, according to STUDER, can 
even contract themselves, a characteristic of the entire genus Gersemia (sensu MOLAN- 
