56 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 
Mr. Gravety’s Reporr. 
Mr. F. H. Gravely, Demonstrator of Zoology in the 
University of Manchester, who occupied the Work-Table 
of that University during a considerable part of July 
and August, has sent me the following note upon some 
of the observations made in the course of his work :— 
“The most striking feature of the animal life 
between tide-marks at Port Krin during July this year 
(1908) was its remarkable scarcity; this was the more 
noticeable after its unusual luxuriance last year. I again 
visited the colonies of Z’ubularia indivisa, var. obliqua, at 
Port St. Mary; only a single hydranth could be obtained 
that bore any gonophores; these, however, were female 
and all of the ‘ obliqua’ type. In connection with these 
I ought to correct one statement in my last*year’s report: 
there is no histological difference—except such as is 
connected with the absence of radial canals—between the 
male gonophores of this variety and those of the normal 
7’. indivisa. My failure to find the * conspicuous sterile 
cells in the outer layers of sperm’ in the normal 
gonophores was due to the fact that the only specimens 
of these gonophores, that I had then seen sections of, 
were ‘not sufficiently well preserved to show them. 
“Since the last report was sent in I have made a 
special study of the gonophores of T'ubularia laryna from 
the neighbourhood of Port Krin, and can now state what 
I only suspected then: that all the hydranths I collected 
last year, both from the breakwater and from the Calf 
Sound, are hermaphrodite; and, further, that a single 
gonophore even not infrequently shows spermatogenesis 
going on at the same time as oogenesis and embryonic 
development. Although every specimen I have found at 
Port Erin shows this condition, those from other localities 
appear to be dimcious, as they have always been believed 
