144 G. T. HARRIS ON THE COLLECTION AND 



obvious drawbacks, shore collecting will appeal to the amateur 

 collector rather than the more professional method of dredging. 

 It entails less expense, requires less intimacy with the local 

 conditions, and, for a given amount of time expended, probably 

 yields a richer harvest ; finally, the physiological effects of shore- 

 collecting are not so overwhelming as are those sometimes 

 connected with dredging. At the same time, no serious student 

 of the Hydroida can ignore the dredge as a means of collecting, 

 as a large number of species can only be obtained by its aid. 

 However, for the reassurance of those who confine themselves to 

 shore collecting, I may state, as the result of long experience, 

 that on a favourable shore the number of species to be found 

 between tide-marks is very great, and amongst them are many of 

 the most beautiful forms amongst the Hydroida. - 



Unfortunately no precise directions can be given for successful 

 shore collecting. It is entirely a matter of experience, and even 

 the practised collector may fail dismally until he has learnt the 

 shore upon which he is engaged. Why hydroids should be found 

 plentifully in a certain section of shore, yet be absent from the 

 same shore a quarter of a mile away, with apparently the same 

 conditions, I am unable to say, yet such appears to be the case. In 

 my own district, where rock-pools are plentiful, I have a case 

 in point. Coryne vaginata, one of the commonest littoral 

 hydroids along the south coast, occurs in two or three of the 

 larger pools of a certain locality, yet although the rock-pools to 

 the right and left for some distance are, as far as I can see, 

 identical, no Coryne occurs in them. Nor is this accidental, or 

 peculiar to one season, as I have been able to go to these 

 particular pools for the last six years with the certainty of 

 obtaining Coryne vaginata. Some years ago when collecting at 

 Criccieth, in North Wales, I spent day after day laboriously 

 trying to collect hydroids where none grew ; finally, I transferred 

 my operations to a less likely looking section of the shore, and 

 collected hydroids during the remainder of my visit over a very 

 limited area. An instance singularly illustrative of this elusive 

 quality of shore collecting recently came under my notice, which 

 may serve to impress upon inexperienced collectors the desirability 

 of not jumping too hastily to the conclusion that they are on a 

 barren shore. A party of professional naturalists spent the 

 whole of one summer in investigating the fauna of a certain 



