586 SCIENTIFIC RECORD FOR 1884. 



were made between July 20 and September 13. Sixty-nine dredgings 

 were made. Of these, five were in depths between 2,000 and 2,G00 

 fathoms and the rest in less deep water. The results were "highly 

 satisfactory, both in the way of physical observations and zoological 

 discoveries." Large numbers of additions were " made to the fauna, iu- 

 ckuling representatives of nearly all classes of deep-sea animals. Many 

 pelagic species were also secured in surface nets, and especially in the 

 trawl- wings. Among these there are some new forms, and many of 

 them have previously not been observed so far north and near tbe Gulf 

 Stream." 



The deep-sea deposits were especially noteworthy. " The bottom be- 

 tween 000 and 2,000 fathoms, in other regions, has generally been found 

 to consist mainly of ' globigerina ooze,' or sometimes of a mixture of 

 globigerina and pteropod ooze. Off our northern coast, however, this is 

 by no means always the case. The ooze is always mixed with some 

 sand and frequently with much clay-mud. In a number of instances 

 the bottom, between 500 and 1,200 fathoms, has beeu found to consist 

 of tongh and compact clay, so thoroughly hardened that many large 

 anguhir masses, sometimes weighing more than fifty pounds, have beeu 

 brought up in the trawl." 



The animals obtained were sometimes of singular interest. " Many 

 additions to the fauna of great depths were made, and a large portion 

 of them are undescribed forms. Some of the fishes were of great inter- 

 est. Huge spiny spider crabs {Lithodes Agassizii) over three feet across 

 were taken in 1,000 to 1,230 fathoms, and another very large crab 

 {Gerijon quinquedens) occurred in great abundance in 500 to 1,000 fath- 

 oms." aSTumerous species of handsome shrimps, many "of a brigiit color 

 and some of very large size, occurred as usual in the deeper di edgings. 

 Some of these had not been taken before." 



Of tiie Echinoderms, the star-fishes were numerous, and two species 

 of a very singular genus, called Brisinga^ were obtained in many locali 

 ties, sometimes in large numbers. Ophiurans of many species were 

 also obtained in numerous localities. {Am. Journ. Sc. (3), xxviii, pp. 

 378-384.) 



Origin (^f the deep-sea fauna. — In a monograph of the Pourtalesiidai, a 

 family of dee[> sea Echinoidea, Professor Sven Loven has expre sed some 

 thoughts respt cting the origin of the deej^-sea fauna, and suggested how 

 the forms characteristic of the depths may have been evolved, distrib- 

 uted, and modified from species of the littoral zone. 



"In the adult state most of the marine evertebrates remain in their 

 native station, wandering within its precincts. Their embryonic and 

 larval age is their period of dispersal. Of numerous littoral forms, of 

 different classes, tribes, and orders, currents must occasionally carry 

 away the free swimming larsTe far into the sea, and during the course 

 of succeedinsf generations early stages of many a species will have in this 





