MARINE BIOLOGICAL STATION AT PORT ERIN. 57 



exhausts or alters some essential constituent of the 

 environment so as to prevent its own continued existence, 

 in quantity, at that spot, but leaves the ground suitable, 

 or even favourable, to the physiological needs of the other 

 set of competing organisms. 



L.M.B.C. Memoirs. 

 No further Memoirs since No. XIX, Polych.et 

 Larv.e (the young stages of the Higher Worms) at Port 

 Erin, by Mr. F. H. Gravely, M.Sc, have been published. 

 BucciNUM, the large whelk, by Dr. W. J. Dakin ; and 

 Pagurus, the Hermit Crab, by Mr. H. G. Jackson, will 

 be ready for publication this winter; while Doris, the 

 Sea-lemon, by Sir Charles Eliot; Sagitta, the Arrow- 

 worm, by Mr. Harvey; Sabellaria, a tube-building 

 Annelid, by Mr. A. T. Watson, and other Memoirs are 

 also far advanced ; and we hope to have a Memoir on our 

 Irish Sea Species of Ceratium and other Dinoflagellata 

 from Professor C. A. Kofoid, who did some work on the 

 local material during his visit to our laboratory in 1908. 

 The following shows a list of the Memoirs already 

 published or arranged for : 



I. AsciDiA, W. A. Herdman, 60 pp., 5 Pis. 

 II. Cardium, J. Johnstone, 92 pp., 7 Pis. 

 III. Echinus, H. C. Chadwick, 36 pp., 5 Pis. 

 IV. Codium, p. J. H. Gibson and H. Auld, 3 Pis. 



V. Alcyonium, S. J. Hickson, 30 pp., 3 Pis. 

 VI. Lepeophtiieirus and Lern.ea, a. Scott, 5 Pis. 

 VII. LiNEus, P. C. Punnett, 40 pp., 4 Pis. 

 VIII. Plaice, F. J. Cole and J. Johnstone, 11 Pis. 

 IX. Chondrus, 0. V. Darbishire, 50 pp., 7 Pis. 



X. Patella, J. P. A. Davis and H. J. Fleure, 4 Pis. 

 XI. Arenicola, J. H. Ashworth, 126 pp., 8 Pis. 

 XII. Gammarus, M. Cussans, 55 pp., 4 Pis. 

 XIII. Anurida, a. D. Imms, 107 pp., 8 Pis. 

 XIV. Ligia, C. G. Hewitt, 45 pp., 4 Pis. 



