INTRODUCTION 3 



and assistance, upon a well selected spot, at a properly judged time, duly 

 authorized and financed, is a stroke of fortune which falls to the lot of 

 few investigators. Add to this all the dangers, risks, accidents, delays, 

 losses, or other unfavourable circumstances occasioned by adverse external 

 physical conditions, storms, irregular seasons, boats, engines, apparatus, 

 and the like, together with the intrinsic difficulties of the problems them- 

 selves, and some conception of the reason why we know so little may be 

 grasped by the layman, indeed he may feel a degree of satisfaction that 

 we have been able to learn so much. 



P^ Literature — " A Bibliography of Publications in the English Language Relative to 

 Oysters and the Oyster Industries " (See Bibliography, 1894), gives the titles of 546 sepa- 

 rate publications l3etween the years 1665 and 1894, only 28 of which antedate the year 

 1850. EHminating those devoted to anatomy, distribution, culture, gastronomies, 

 greenness, resting position, the happiness or the morals of the oyster, odes to an oyster, 

 popular natural history society and magazine articles that do not represent original 

 research, extracts, sj^nopses, reprints that repeat but do not add information, and other 

 rather unimportant or irrelative types of literature, we find that the effective contri- 

 butions are wonderfully reduced in numbers, although it may be as Horst has stated 

 (1884) that "more has been A\Titten on the history of the development of the oyster 

 than on that of any other invertebrate." 



Broadly speaking, we may state that oiu- knowledge of the development of the 

 oyster began to be acquired in Europe by at first somewhat vague, disconnected, and 

 scrappy observations on the European species {Ostrea edulis L.), in some of the most 

 progressive countries bordering on those parts of the Mediterranean sea, the Atlantic 

 ocean and the North sea, where this oyster abounds. Italy, England, Holland, Den- 

 mark, France, Germany, and some other countries made irregular, occasional contri- 

 butions until, at a later time, corresponding with a greater degree of national peace, 

 leisure, desire for knowledge, need to make use of natural products, improvement of 

 instruments, and design in methods, such isolated, superficial, quaint observations as 

 those of Sprat (1669) gave way through Brach (1690), who first used the microscope to 

 observe the eggs and larvae of the oyster, Leeuwenhoek (1695), who discovered the 

 spermatozoa and the velum, Baster (1759), Home (1826), to Davaine (1852), who was 

 the first to offer a detailed account and observed the nucleus, blastomeres, shell, liver, 

 intestine, branchiae and heart, and to Lacaze-Duthiers (1854), who in some respects 

 supplemented the preceding, found the mouth and anus, lower lip and otoliths. Then 

 followed Coste (1861), De la Blanchere (1866), Gwjoi-Jeffreys (1869), Saunders (1873), 

 Salensky (1874), Mdbius (1877), Bouchon-Brandeley (1882), Horst (1882, 1884), Hub- 

 recht (1883), Huxley (1883), and Hoek (1884), of which the papers by Horst and by 

 Huxley mark a distinct progress for completeness and accuracy. 



Already the scene of greatest activity had changed to America, where Brooks 

 (1879), Ryder (1881), Rice (1883), Winslow (1884), Jackson (1888), Nelson (1888), 

 and others, accessible to the greatest natural oyster-producing waters of the world, en- 

 thusiastically entered into the details of development, artificial fertilization and culture 

 of the American oyster (Ostrea virginica Gmelin). 



Sexes Distinct in American Oyster.— Unlike the hermaphrodite Euro- 

 pean oyster, in which the eggs and early stages of development are 

 retained within the mantle cavity of the parent until they reach a size 

 of 0.15 to 0.18 mm. and have a shell, the unisexual male and female 

 American oysters expel their spermatozoa and ova into the sea water, 

 where fertilization and all stages of development take place. 



This discovery, due to Brooks, together with his sound scientific 

 methods, set a new standard for research, added immensely to our 

 comprehension of the earlier stages of development, opened a way to 

 progress in artificial culture, and communicated an enthusiasm to co- 



