[39] CONSTRUCTION AND WORK OF FISH-HAWK. 41 



fathom line, the larger proportion being new additions to the fauna of 

 Southern New England, and including at least 5 new genera and IS new 

 species. One interesting form was the pole flounder, common in the 

 deeper parts of Massachusetts Bay and the Gulf of Maine, and of which 

 both young and adult individuals were secured. 



At each dredging station, collections were made with the towing net, 

 which is designed to scoop in the free-swimming forms, living at the sur- 

 face and at intermediate depths. It was used at the surface, at depths 

 of 5 and 10 fathoms, and near the bottom, for the latter purpose having 

 been attached to the dredge line a short distance above the dredge or 

 trawl. The animals obtained by this means were mostly jelly fishes, 

 pteropods, heteropods, salpse worms, larval crustaceans of the higher 

 orders, and copepods, the latter frequently occurring in countless num- 

 bers. They serve as food for the surface-swimming fish, such as the men- 

 haden and mackerel. 



Many of the species found in this new faunal region are arctic, or be- 

 long to the colder waters of the Atlantic coast of Europe, or to the Med- 

 iterranean. Others again are more tropical, being related to southern 

 or West Indian forms. Some of the commoner forms of Crustacea and 

 echiuoderms are identical with species described from off the Florida 

 coast. The surface species belong mainly to the Gulf Stream fauna. 



The mass of material taken on these three trips was very great, fill- 

 ing several hundred jars, and a greater number of small bottles and 

 homoeopathic vials, as well as many large tanks. The lirojDcr working 

 up of this material requires the expenditure of much time and labor, and 

 while several hundred species have already been recognized and de- 

 scribed, large quantities of the smaller and more obscure forms still await 

 elaboration. 



The few dredgings made November 16, off the mouth of Chesapeake Bay, 

 in depths of 1^ to 300 fathoms, gave very interesting results, especially 

 in the greater depths, where nearly all the species secured were identical 

 with those from the more northern localities, the character of the bottom 

 being also the same. A large amount of material was obtained for a 

 single day's work. All the species have not yet been worked out, but the 

 identifications, so far as they have been made, indicate that the several 

 groups of invertebrates are represented by about the following number 

 of species : The mollusca by 48 species, including three sj^ecies of squids 

 and two of Octopm-, the echiuoderms by 19 species; the polyps by 6 

 species ; and the hydroids by two species. The singular tube-dwelling 

 worm of the north, Hyalincecia artifex, was also very abundant in this 

 region, as were other associated species of worms. 



Synopsis of the steam log of the United States Fish Commission steamer Fish 

 HawlCjfor the year ending December 31, 1880. 



Stroke of i)iston in feet 2J 



Number of condensing cylinders 2 



Diameter of condensing cylinders in inches 22 



