﻿300 Proceedings of the Royal Physical Society. 



XXV. Some Medusce and Cteno^phores from the Firth of Forth. 

 By Wm. Evans, F.R.S.E., and J. H. Ashworth, D.Sc. 



(Read 21st December 1908.) 



On 27th June last — which was an ideal midsummer day, 

 being calm, bright, and warm — we went to Dunbar for the 

 purpose of collecting marine invertebrates. On our arrival 

 at the harbour we found, swimming alongside the quay and 

 among the fishing boats, swarms of small medusae and cteno- 

 phores, a considerable number of which we captured by the 

 aid of net and bucket. The collection was noteworthy for 

 the beauty of form and colour of the various organisms, 

 especially striking being the constant play of rainbow colours 

 along the combs of the ctenophores. With the exception of 

 an extremely fragile bilobate ctenophore, afterwards identified 

 as Bolina infundihulum (Fabr.), specimens of the different 

 species obtained were preserved in formalin (6%) for further 

 examination. It was, however, found impossible to fix any 

 specimen of Bolina. Various strengths of formalin were 

 used, but with the invariable result that dissolution of the 

 specimen took place within a few seconds of the application 

 of the fixative. On a subsequent occasion, a chrom-osmic 

 mixture (chromic acid 1%, 100 parts, osmic acid 1%, 2 parts) 

 in large volume was used with scarcely better results. 

 Similar failure has, it appears, been the experience of others 

 who have attempted the preservation of this beautiful 

 ctenophore. 



With the view of supplementing the observations made 

 on 27th June, one of us (W. E.) revisited the harbour at 

 Dunbar on a number of occasions during the succeeding six 

 months, and obtained a few additional species, including the 

 interesting medusa Tima hairdii (Johnst.), which he has also 

 found during the present month (December), along with an 

 Aeqicorea, in the harbour at Burntisland. 



To Edward Forbes, Sir John Dalyell, and Strethill Wright 

 we are indebted for a few early records of medusae and 

 ctenophores from the Firth of Forth, but very little has 

 since been added to our knowledge of the species occurring 



