THE COPENHAGEN MUSEUM AND OTHER SOURCES. 397 



invertebrates, a reporter can scarcely pursue his studies very far without finding that 

 there arc new forms to be described, new names to be applied, new items of classification 

 to be introduced. For all these the rule above mentioned requires double publication, 

 and this, unlike the quality of mercy, wdiich blesses him that gives and him that takes, 

 is an almost unmitigated nuisance to the writer and the reader. 



It now remains for me to express my hearty thanks to Dr. Meinert and his colleagues 

 at the Copenhagen Museum, and especially to Dr. H. J. Hansen, for entrusting me with 

 the fine collection of Orchestiidii? under their charge. To the Trustees of the Australian 

 Museum, Sydney, I am indebted for ' co-types ' of some of Professor Haswell's species sent 

 me through the obliging intervention of Mr. R. Etheridge and Mr. Thomas Whitelegge. 

 From America specimens of great service to my work have been sent me by Mr. James 

 Benedict, of the National Museum, Washington ; by Mr. S. J. Holmes, of the University 

 of California ; and by Mr. C. F. Baker, of the Alabama Polytechnic Institu.te. To 

 Professor Mobius I owe my thanks for examples of several of the Lake Baikal Gammarids. 

 Mediterranean specimens received from my friends M. Ed. Chevreux and Signor Delia 

 Valle have thrown light on various obscure parts of the subject. Lastly, I must refei" 

 to the special kindness of Professor HaswcU, F.E.S., and Mr. Thomas Whitelegge, who 

 have sent me miscellaneous gatherings of Australian Amphipoda, enabling me to 

 dredge for southern rarities under the shelter of my own I'oof in the peaceful shallows of 

 a watch-irlass. 



Fam. OECHESTIIDaE. 



Sijnopfic Tleic of the Genera. 



, f ^laxillipeds, fourth joint of palp wanting or quite rudimentaiy, 3. 



y Maxillipcds, fonrtli joint oi^ palp distinct, o. 

 First gnathopods simple in the male, 3. 

 First gnatliojiods snbehelate in tlie male, 4. 



( Second gnathopods feebly chelate in the male 1. Tnlifrus Latreille, 1802. 



' Second gnatliopods strongly subchelatc in the male 2. Orchestoidea Nicolet, 1849. 



f First gnathopods subclielate in the female 3. Orchest'ia Leach, 1814. 



i First gnathopods simple in the female 4. Ta/urc/icstia J)a.na, 1852. 



^ f Third nropods single-jointed, G. 



( Third uropods not single-jointed, 7. 



f Telson partially cleft 5. Ceina Delia Valle, 1893. 



i Telson entire 0. ChUtonia, n. g. 



^ r Third uropods with two rami, 8. 



*- Third Tii-opods with only one ramus, 9. 



(" Telson divided 7. Par/iyr/Ze Stehhing, 1897. 



I Telson entire 8. Neobiile Haswell, 1880. 



f. f^Iaxillipeds, fourth joint of palp not luiguiform 9. Farorchestia, n. g. 



^ JMaxillipeds, fourth joint of palp ungniform, 10. 



55* 



f Fir 

 iFir 



