TUNICATA OF THE L.M.B.C. DISTRICT. 245 
Leptoclinum durum, Milne-Edwards. 
A small colony of a pale brown colour, probably belonging 
to this species, was collected on the shore at Puffin Island, 
on September 10th, 1888. 
Family. DIPLOSOMIDZ. 
Diplosoma gelatinosum, Milne-Edwards. 
Some colonies were obtained at Douglas in 1886, and 
also on the shore at Puffin Island on July 38rd, 1887. 
They contain stellate calcareous spicules scattered through 
the test. 
ASCIDIA SIMPLICKES. 
Family. CLAVELINID#. 
My original contention that this group, the “ Social 
Ascidians,” ought to be considered as a family of the 
Simple Ascidians, Clavelina being united to Ciona by such 
intermediate forms as Heteinascidia and Rhopalona, has 
received powerful support lately from the investigations of 
Sluiter into the species of Hcteinascidia, and of Roule 
upon Rhopalona neapolitana. Roule has discovered that 
Rhopalona is in every respect similar to Hcteinascidia, 
except that it does not produce buds. 
Clavelina lepadiformis, O. FE. Muller. 
This species was formerly recorded from Hilbre Island 
and the Isle of Man. I can now add the following 
localities at which it has been taken:—Off Colwyn Bay, 
on July 9th and September 7th, 1887, dredged by Mr. 
A. O. Walker, in two fathoms; off Groudle Bay, north of 
Douglas, Isle of Man, dredged by Mr. J. Clubb in August, 
1886; under stones on the South Spit, Puffin Island, 
collected on July 3rd, 1887, and September 8th and 9th, 
1888. 
