ON THE MARINE BIOLOGICAL LABORATORY, PLYMOUTH. 271 



Invesligatio7is made at the Marine Biological Jjoboratory, Plymouth.- — 

 Report of the Gommitiee, consisting of Mr. W. Garstang {Chairs 

 man and Secretary), Dr. E. Ray Lankester, Professor Sydisey 

 H. Vines, Mr. A. Sedgwick, and Professor W. F. R. Weldon. 

 (Brawn up by the Secretary.) 



The British Association's table at the Plymouth Laboratory has been 

 allotted during the past year to the following naturalists : — 



Mr. H. M. Woodcock, B.Sc. Lond. (University Scholar), for an inves- 

 tigation of the Life-history of Sporozoa (one month) ; and to 



Mr. G. W. Smith, New College, Oxford, for an investigation of the 

 Anatomy of certain Tunicata (three weeks). 



The applications received for the use of the table have exceeded tlie 

 limit placed upon the Committee's powers of appointment by the funds at 

 their disposal. The Committee therefore invite reappointment, together 

 with a grant sufficient to maintain a table at the laboratory for a period of 

 six months (301.), in order to enable Mr. Woodcock to continue his in- 

 vestigations of the Life-history of Spoi^ozoa, to enable Mr. G. W. Smith 

 to begin an investigation of the Sense-organs of Fishes, to enable Mr. 

 W. Wallace, of St. Andrews University, to investigate the variation of 

 the fins in Elasmobranch fishes, and to enable other competent naturalists 

 to perform definite pieces of work at the Plymouth Laboratory. 



Mr. Smith will occupy the table during July. 



Mr. Woodcock's Report is appended below. 



3Ir. Woodcock's Beport. 



I occupied the British Association's table for one month in April and 

 May 1902. My particular objects were two. One was to further inves- 

 tigate some curious bodies which I had noticed attached to the inner side 

 of the mantle — near the apex of the flap — in Pecten opercidaris, and also 

 attached to a gill filament of the same specimen. The other was to find 

 further stages in the life-history of Gregarina irregularis, occurring in the 

 blood-vessels of HoloiJmria nigra at Plymouth. 



In most of the Holothuria which I had the opportunity of examining 

 the gregarine was present. In about six instances I found it in the cavity 

 of the blood-vessels, motionless, but easily movable on gently pressing. 

 It was not easy to get them out of a blood-vessel unchanged in shape, 

 for the least touch seemed to distort or make them irregular. Those that 

 were safely liberated were regular in shape, though not uniform. Some 

 ■would be broader and shorter, others longer and narrower, but all more 

 or less oval in outline. 



Observed living, they were white and opaque, but when stained and 

 cleared they all showed two vesicular nuclei, separated by a distinct 

 septum. 



The other stage, largely preponderating in numbers, in which I found 

 the gregarines was as little white vesicles attached to the blood-vessel by 

 thin stalks. These vesicles, as already described by Professor Minchin,' 

 consist of the evaginated wall of the vessel, containing the rounded 



> Q.J.M.S., vol. xxxiv. 1893, p. 279. 



