166 ME. E. T. BEOWNE — BISCATAN PLANKTON : 



Previous Records eor the Bat of Biscay. 



In searching for records of medusae taken far away from shore in the Bay of Biscay I 

 have not heen very successful, and have prohahly failed to find some that have been 

 made. In the Report by Maas (1904) on the collections made by the Prince of Monaco 

 there are three records for the Bay, namely, JEquorea forsTcalea, Agliscra elata, and 

 Atolla bairdii. These were all found on the southern side of the Bay, off the north 

 coast of Spain. 



On Collecting and Preserving Medusa. 



The following methods for collecting and preserving medusae have been used by me 

 for several years. I publish them now with the hope that they may be useful and helpful 

 to naturalists who go abroad to collect plankton, or to make general collections, and, 

 finding some medusae, would like to know how to preserve them in fairly good condition. 

 I take into consideration the difficulties of working in a limited space on board a ship, 

 and also in having to get through the work with limited chemicals, vessels, and time. 

 On this account I omit methods more suitable for use in a properly equipped laboratory 

 on shore, and methods suitable for histological work. 



Collecting Iledusce. — A small flat hand-net made of bolting-silk is a useful implement 

 for catching medusae which can be seen swimming at the surface. Its use, however, is 

 practically limited to a small boat in sheltered waters. The medusae can be gently 

 lifted from the sea, and at once placed in a jar of sea-water without receiving any 

 damage. 



Of tow-nets there are many kinds, some of which are responsible for the mutilation 

 of jelly-fish. The best kinds are those with a long cone-shaped net with a can attached 

 to the end. The bad kinds are those without a can at the end, and, worst of all, are 

 certain kinds of closing-nets. 



As a guide, I give the size of the net which I generally use from a rowing-boat. It 

 has a circular mouth of 17 inches in diameter, and the net is about 5 feet in length, 

 gradually tapering down to 3^ inches in diameter, which is the diameter of the zinc can 

 attached to the end of the net. The nets are made of bolting-silk. Three nets form the 

 series, having respectively 30, 50, and 76 threads per inch. It is a mistake to use a very 

 fine-meshed net (about 150 threads per inch), unless one is seeking for diatoms and other 

 microscopic organisms. 



The old-fashioned bag-shaped net, without a can at the bottom, is very liable, unless 

 pulled very slowly through the water, to damage delicate animals. The plankton 

 collects in a mass at the bottom of the net, and the pressure of the water against this 

 resisting mass crushes and mutilates the specimens. 



The closing-nets used for deep-sea investigations, and worked by various mechanical 

 devices for opening and closing the mouth, are frequently made so that when the mouth 

 is closed the sides of the net come together. It appears to me that in hauling up the 

 net from great depths, especially when the ship is rolUng, the sides of the net rub 

 together, and consequently the animals inside get seriously damaged. The medusae 



