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A HISTORY OF ESSEX sufficiently examined to decide whether it was a different species or only a variety. 4. Cyanea lamarckii. In July, 1888, this was very abundant in the Aide at Shingle Street, and I think I have seen it, or an unusually blue C. capillata, in the Stour or Colne, but so many years ago that I am not certain, and the specimens were not caught and examined carefully. In any case it seems to occur only now and then. 5. Cyanea imporcata, A. M. Norman. On July 26, 1884, I caught in the Colne off Mersea a medusa of a beautiful purple- blue colour. At that time I was studying the spectra of the colouring matters of marine animals, and after making a careful drawing I destroyed the specimen in studying the pigment, not knowing that it was such a rare species. In the seventeen subsequent years I have looked in vain for another specimen. On sending my drawing to Mr. Garstang, he recognised it as a Cyaneid medusa, on account of the sixteen radial gastric pouches indicated in my figure, the deep and much folded oral membranes, the absence of marginal tentacles and the presence of eight crescentic groups of tentacles attached to the under side of the disk at some distance from the edge. The tentacles are seen to be of various lengths, but many exceed twice the length of the oral appendages. The medusa, on the other hand, differs from the common Cyanete of our coasts in the cup-shaped disk, the diameter of which is less than twice the height. In this re- spect the medusa closely resembles the Cyanea imporcata of Norman (Nat. Hist. Trans. Northumberland and Durham, 1865, i. 58 60, pi. xi.), of which only a single specimen has hitherto been recorded, and that also in the North Sea, between the Dogger Bank and Newcastle. Mr. Garstang believes the two to belong to the same species, although my specimen was probably devoid of the super- ficial markings on the disk which Norman figured, and which he tentatively but errone- ously described as radiating and secondary canals. Possibly the species inhabits the deeper waters to the north of our islands, from which region stray specimens have drifted from time to time down our east coast. Further information is much to be desired to clear up several doubts connected with this species, which is evidently very rare in the English seas. 6. Aurelia aurita (Linn.) Though there seems to be a great variation in number in different years, yet on the whole this is by far the most common medusa on the coast. Occasionally it is extremely abundant. By far the larger number are under 6 inches in diameter, but those of at least double that size are sometimes numerous in the latter part of the season. I have col- lected and preserved a considerable number of abnormal varieties, differing much in the number of the different organs. 1 . Rhizostoma octopus. Linn. I have occasionally seen very fine speci- mens in the Wallet and in the Swin. I have collected many small ones in the Crouch at Burnham and one in the Colne, but none in any other of the Essex estuaries. II. CTENOPHORA Jellyfish devoid of a muscular umbrella and provided with eight vertical (meridional) rows of iridescent paddles. Pleurobrachia pileus, Modeer. Formerly common at most places, but during the last few years has become less and less abundant, and in 1900-1 comparatively scarce. The best way to preserve it is to take it out of the water by means of a sieve, and put it at once into diluted formalin. Trawled or dredged specimens are almost worthless. I have a mounted specimen which had been swallowed by another only a little larger. III. ANTHOZOA (Sea Anemones and Corals') Nomenclature : Gosse, British Sea Ane- mones and Corals (1860). 1. Alcyonium digitatum, Linn. The only locality in which I have found this is in the open water off Harwich, never having dredged it in the estuaries. Mr. Un- thank has met with it in the Wallet. 2. Actinoloba dianthus, Ellis. The white, the flesh-coloured and the brown varieties all occur abundantly in the Crouch at Burnham, attached to large stones on the south shore, and can be easily ob- tained when the tide is very low. Some years ago I found some on the oyster beacons in Pyefleet, but I have not seen any for several seasons. The white and the flesh- coloured varieties are abundant on the timber of the pier at Harwich, but are exposed only when the tide is very low. By using men- thol it may be killed and preserved in a fully expanded condition.