6 MARINE INVERTEBRATA OF GRAND MANAN. 



number of workers. But these it is hoped will be furnished by the increasing taste 

 for pursuits of this kind in our country. The records of depths and stations may 

 seem trivial in the eyes of some, but upon their accumulation depends the decision 

 of several important questions. 



It will be observed that the number of new species described in this paper is 

 quite large. This naturally results from the fact that so few families of our 

 marine invertebrates have yet been investigated. Thus, with the exception of 

 the shells, nearly every species required special study to determine its genus, and 

 whether it was, or was not, identical with some European or Arctic species. 



Pelagic animals are particularly abundant at Grand Manan, on account of the 

 proximity of deep water, and by far the greater part of the species were obtained by 

 the use of the dredge. Dredging in this region is attended with dangers, to guard 

 against which some little foresight is necessary. The boat should always be provided 

 with a compass, even in going short distances from land, as the fogs are very thick 

 in summer, and are suddenly formed. The dredger must also keep an eye to wind- 

 ward, as the approach of a fog bank may be generally seen at least some minutes 

 beforehand, so that a course may be taken for home ; unless, indeed, he be some- 

 thing of a pilot himself, or have one with him, when he may often continue his 

 operations notwithstanding the obscurity. A "horn," consisting of a Siromhus 

 gigas with the apex knocked off, should also be provided, to be used when lost in 

 a fog, for, when blown, it will be answered according to the humane custom of this 

 region, by any who may hear it, whether on shore or in boats. In many places, 

 there are patches of rock on the sea-bottom, where the dredge is very liable to be 

 caught. Usually, it may be disengaged by heaving in a portion of the dredge- 

 warp, but this is often not sufficient. The only means then remaining of recover- 

 ing it is to slack out all the line, while the boat is brought round and run in a 

 direction opposite to the former course. It may even then occur that the dredge 

 remains fixed, so that, on an excursion to these islands, two or three should always 

 be provided. 



I must here express my grateful acknowledgements to Professor Agassiz, for the 

 use of his valuable collection of European books and specimens, which he most 

 liberally allowed me, while as his pupil I had the pleasure of his society and the 

 advantages of his instruction. To the officers of the Smithsonian Institution I am 

 also greatly indebted, for affording me every possible assistance in the use of rooms, 

 instruments, books, etc., while this paper was in preparation. I am also indebted 

 to Professor Dana, for his kindness in giving me tracings of the details of many of 

 his new genera of Crustacea, which have materially aided me in the determination 

 of those herein described. 



Suites of the original specimens, from which the new species in this paper were 

 described, are deposited in the Museum of the Institution, and in the cabinet of 

 Professor Agassiz, at Cambridge. 



Outline figures are given in the plates of some of the most interesting species, 

 especially such as form new genera. 



WILLIAM STIMPSON. 



Smithsonian Institution, Februari/, 1853. 



