168 THE CANADIAN NATURALIST... [Vol. Vli^, 



GENITALIA AND EMBRYOLOOGY OF THE BRACHIOPODA. 

 By Prof. Edward S. Morse, of Salem, Mass. 



The papers read ou this subject by Prof. E.. S- Morse^ of" 

 Salem, Mass, showed that the brachiopod.^5 were the only class oC 

 animals of which the developmental history has been hitherto- 

 unknown. So dark has been this department of zoology, that 

 an eminent German naturalist, Oscar Schmidt,, published but 

 a single figure of a young brachiopod as an important con- 

 tribution to existino- knowledge. Lacaze-Duthier had been the 

 only one to give a few figures of an embryo braxhiopod until. 

 Prof. Morse last year contributed sketches of a native species^. 

 confirmino; the investigations of the French naturaiist.. 



Before going further it may be well to give unscientific readerr. 

 a notion of what kind of an animal the brachiopod is, and why 

 so great interest centres upon this group. One of Cuvier's me- 

 moirs, as early as 1 802, was upon one of this class of animals.- 

 Hancock and Davidson of Enojland have eacli received aold 

 medals from the Royal Society for their contributions on this^ 

 subject. Eminent German naturalists have written memoirs-^ 

 upon it. Prof. Huxley has made it the subject of special study^. 

 The reason for this peculiar interest among naturalists is that 

 the very earliest fossiliferous remains — those deposited in the 

 most ancient rocks — are members of this class. They are more- 

 over found in rocks of all subsequent ages, and are still living ib- 

 the seas of the present day. Singularly enough, while all other- 

 groups of animals have changed in their distinctive fea^ures^ andl 

 many have become extinct, there are brachiopods of the present 

 day that can scarcely be distinguished from their most ancient 

 representatives. They are a closed type^ having no branches 

 and may be therefore considered as a royal fiimily among ani- 

 mals, their line of descent having been unbroken, and untainted 

 since the very dawn of life. But like other ancient families^. 

 their numbers have seriously diminished, and. their line is pro- 

 bably in process of extinction. 



The brachiopod is a small animal, enclosed m a bivalve shell 

 and adhering by a posterior appendage to the ocean, floor The 

 possession of this bivalve shell has led all naturalists to indude- 

 brachiopods among the mollusks. Three years ago Prof. Morse- 

 after a long and patient study ^of the living forms, startled tliet 



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