44 Prof. Mcintosh's Notes from the 



setts for twelve successive years, and invariably found that 

 in the earlier part of the summer the majority were small and 

 not yet filled with eggs, as they are later in the season. The 

 largest specimens, he adds, are always seen during the last 

 summer months, and all disappear after the autumnal gales. 



On the eastern coast of Scotland the most abundant Cteno- 

 phore at the beginning of the year, that is in January, is 

 Pleurobrachia, which frequents the lower parts of the water, 

 as demonstrated by the use of surface-, midwater-, and bottom- 

 nets. This to a certain extent had long been known, for it 

 is more than thirty years since the late Prof. G. E. Day exhi- 

 bited to his class at St. Andrews in December living speci- 

 mens gathered on the West Sands by Miss Otte. Moreover, 

 the presence of small as well as large examples in the nets 

 indicates that the ranks are being gradually recruited as well 

 as by-and-by supplanted by the younger forms. There is 

 little evidence of a general destruction of the adult forms at 

 a given period. 



The irregularity in size of those procured in January in all 

 probability arises from the length of time during which 

 spawning is carried on. The species continues in great pro- 

 fusion in February, and free (pelagic) ova were not uncom- 

 mon — similar features characterizing the southern waters, as 

 at Sheerness-on-Sea *, at this time. In March it was as 

 plentiful both in the midwater- and bottom-nets, though the 

 majority of the examples were small, a few, however, reaching 

 | inch in long diameter. Many minute young abounded in 

 the trawl-like bottom-net towards the end of the month. 



Like the other pelagic Coelenterates, Pleurobrachia became 

 very prominent in the midwater-net in April ; but the speci- 

 mens were chiefly small. At the beginning of May the size 

 of the hordes of small Pleurobrachice ranged from | to ^ inch 

 in long diameter ; but they were accompanied by many larger 

 forms, the number of the latter showing an increase on the 

 previous month, a condition in St. Andrews Bay that may, 

 however, have been due to immigration from the offing. 

 The larger forms were mature. The majority were captured 

 by the midwater-net, so that they had frequented the deeper 

 regions of the water. 



h\ July ova, larvai, and young of Pleurobrachia were 

 common near the bottom of the water, and towards the middle 

 of the month ova and larvas appeared in the midwater-net and 

 by-and-by at the surface, the diameter of the latter varying 

 from 1 to 1*5 millim. In every haul of the midwater- and 



* From observations kindly furnished by Mr, Shrubsole. 



