HARD WICK& S SCIENCE- G SSI P. 



173 



of the capsule have been compressed laterally in 

 course of development, hence their more or less 

 hexagonal form ; but the apparently specialised cells 

 have been more at liberty to follow what may be 

 designated the inherent law of circularity. 



In O. diaphanum (Fig. 96), and some others, the 

 epidermal orifice is often very large and admits of the 

 entrance and lodgment of one or more stray spores, 

 a circumstance productive of considerable confusion 

 until the eye has become well accustomed to what is 

 being sought for. Further, the orifice varies much 

 in size in the same capsule, and in this respect, again, 

 forms no guide to the species. Dr. Braithwaite 



Fig. 100. 



figures it large in 0. anomalum, and I find it small in 

 O. saxatik (Fig. 97), which {fide Braith.) is the same 

 species. 



In O. rivulare (Fig. 98), the orifice is very small and 

 the differentiation in the adjacent cell-walls is less 

 marked, but whether this is the case in other species 

 with the opening uniformly small I have not at 

 present the opportunity of judging. 



Fig. 95 represents a section of the underside of a 

 leaf of the common wild ivy. Fig. 99, the same of 

 the lily of the valley. Fig. 100, of the caper spurge 

 (Euphorbia lathyris). The stomata are shown in all 

 three. W. P. Hamilton. 



Shrezvsbury. 



OYSTERS. 



ONE of the greatest difficulties which an author 

 has to face is to find appropriate titles for his 

 books and papers ; this may seem to be a matter of 

 trivial importance, and easily overcome, but, experto 

 crede, it is often more trying and needs greater cudgel- 

 ling of the brains than the preparation of the work 

 itself. The title unconsciously influences the current 

 of thought and method of treatment, and when an 

 inappropriate one is chosen, the writer finds himself 

 compelled — for the title is his text — to bear it 

 constantly in mind ; and when he has, as he hopes, 

 finished his task, he discovers that it is so little to 

 his liking that he is often forced to begin it anew ; 

 and when he again goes over it, he too often finds 

 that he has not done it justice, perhaps even left out 

 much he meant to say : he is then once more 

 compelled to choose a fresh title and again recast his 

 book, and that means immense labour. We have 

 now lying by us an article on which we have expended 

 a world of trouble, and have several times rewritten 

 it, and at our last revision we chose still another name 

 for it, once more having to recast our work. When, 

 therefore, a circular was placed in our hands from 

 which we learnt that a most exhaustive treatise on 

 oysters was coming out, we could only wonder what 

 happy inspiration had guided the industrious author 

 in his fortunate choice of "Oysters and all about 

 them." We positively envied him the comprehensive 

 character of the title ; half the battle was won when 

 that name was decided upon ; all that relates to 

 oysters, their history, value as food, methods of 

 cultivation, literature — and the subject is one of the 

 vastest known to us — all was in place ; and we could 

 not wonder that eight hundred closely printed pages 

 were needed to cover, not the whole of the immense 

 field, but a part of it, for the author, it appears, has 

 been compelled to hold over a great deal of matter 

 which will hereafter see the light, when another and 

 much enlarged edition is called for. The author has 

 given six years of untiring thought and labour to the 

 opus magnum of an eventful and dignified life, and 

 he has had, in passing the sheets through the press, 

 the invaluable assistance of a most accomplished and 

 highly cultured clergyman, who has most generously 

 devoted many weary weeks and sleepless nights 

 to the revision of a book which is a perfect 

 treasury of interesting and curious information. The 

 author, Dr. J. R. Philpots, was, we are informed, 

 some time ago sheriff of the district in which he has 

 so long resided, and it has occurred to him that his 

 book, in which he was even then engaged, might be 

 so modified and enlarged that it would do the county 

 of Dorset, but more particularly his own town of 

 Poole, lasting service in drawing attention to the 

 value and importance of oyster cultivation and the 

 facilities for the purpose running to waste in the 

 vast sheet of water known as Poole Harbour. Dr. 



