498 Bibliographical Notices. 



The first six chapters, constituting Parti., require little comment, 

 being a semipopular account of the classification of flat-fishes, the 

 history of the genus Solca, and a description of the species with 

 synonymy. It would have been an acquisition to have figured SoJea 

 Greenii. In Part II. the osseous system and the fibrous and muscular 

 tissues are elaborately described, and a somewhat detailed account 

 given of the oblique muscles, their attachments and connexion with 

 the distortion of the eye and orbit. The description of the viscera 

 and vascular system is mainly valuable in connexion with the un- 

 ravelling of the mystery which has more or less shrouded the males 

 and the male organs. It was the exceeding smallness of the ripe 

 testes that had puzzled the non-scientific observer, and even some 

 who could not be included in this class. The life-like half-figures 

 of the male and female by Miss Willis, together with the descriptions 

 of Mr. Cunningham, will be of much service to future workers. An 

 account of the nervous system, the skin and its parts follows, com- 

 parisons of the scales of various species of soles being made by aid 

 of figures. The sense-organs on the under surface of the snout are 

 shown not to differ from those of the dermal tube of the lateral 

 line. 



The sixth chapter of Part II. contains the embryology of the sole. 

 When this was written the author had not seen the ovum immedi- 

 ately after its escape from the ovary, but from a postscript on p. 135 

 he had been more successful this year (1890). Other naturalists, 

 however, had previously seen it at this stage, and agree that it corre- 

 sponds with the condition of such forms as the cod in regard to the 

 protoplasm. He calls the zona radiata the vitelline membrane, but 

 does not refer to his former view that it is an extra-vitelline product. 

 The particles of oil which form a kind of ring in the sole's egg are 

 occasionally somewhat more distinct than shown by the author, and 

 vary a little in size, as described in a previous publication, viz. from 

 •0015 to '0004 inch. He does not now hold the view that oil- 

 globules occur in the perivitelline space. Moreover he now 

 locates the oil-globules beneath the trunk of the embryo sole. He 

 prefers the term "segmental cavity" to Prof. Ed. E. Prince's less 

 ambiguous term " germinal cavity." The pigment of the larval sole 

 immediately after hatching appears to diflFer materially in Scotland 

 (v/f/e Trans. Roy. Soc. Edinb. vol. xxxv. pi. xvii. fig. 13, Feb. 1890), 

 since it is not truly yellow, but dull stone-grey or dull yellowish 

 white, and this afterwards changes into the ochreous hue so charac- 

 teristic of the post^larval sole (vide ' Report of the Scotch Fishery 

 Board,' July 1889, pi. iii. fig. 9). 



The author did not succeed in keeping the larvae alive more than 

 a few hours until this spring (May 1890), and then only till the 

 yolk " was almost absorbed." Elsewhere experience differs, and 

 the sole has been found to be one of the hardiest larva? under treat- 

 ment. He has also overlooked the late larval stage referred to at 

 the end of the previous paragraph ; but he has made an interesting 

 addition in securing a young sole | inch long from Mevagissey, 

 showing most of the features of the adult. 



