VIII ILLUSTRATIONS. 



Facing page. 



A NEW PRINCIPLE OP aquiculTure AND TRANSPORTATION OP LIVE PISHES — Continued. 



Plate XCIX. (19) Detail of propeller shaft couplings. {20) Detail of gears on float at 



junction of transverse and longitudinal shafts 780 



C. (21) Detail of device for throwing propeller in and out of gear. (22) 



Operation of device for throwing propeller out of gear 780 



Apparatus and methods employed at the marine fish hatchery at Flodevig, Norway: 

 Plate CI. (i) Egg collector. (2) Eccentric wheel providing circulation of water 



in hatching boxes 810 



Cultivation of the turbot: 



Plate CII. (i) Turbot eggs with embryo. (2) Larva with vitellus. (3) Larva with 



vitellus almost entirely resorbed — beginning of critical period 870 



CIII. (4) Larva a few days after end of critical period. (5) Detail of pigmen- 

 tation of abdomen of above figure. (6) Larva after critical period. . . . 870 

 New and improved devices for fish culturists: 



Plate CIV. (1) Artificial bass nest. (2) Bass fry retaining screen and trap. (3) 



Collecting tub, with float 1000 



CV. (4) Fish retainer, with float. (5) Fish attendant's outfit — aerator screen, 



plunger, combined ice pick and scaff net 1000 



CVI. (6) Seine for collecting fingerling bass. (7) Shipping case for fish eggs. . 1000 

 Habits and life history of the toadfish, Opsanus tau: 



Plate CVIL (i) Rejiroductive organs of the toadfish. (2) Ventral aspect of ripe ovary, iiio 

 CVIII. (3) One-half of Pinna shell nest, showing live eggs in segmentation. 4) 



Eggs in late segmentation mo 



CIX. (5) Board nest, eggs with late blastoderm and early embryos. (6) Nest 



showing embryos having marked enlargement at one end 11 10 



ex. (7) Pinna shell nest, showing tadpole-like larvae. (8) Board nest. 



Larvse slightly older than in figure 7 11 10 



CXI. (9) PittBo shell nest, late larval toadfish. (10) Late larval toadfish, show- 

 ing color markings mo 



CXII. (11) Same nest as figure 10. The young nearly ready to break away. 

 (12) From instantr.neous photograph of free-swimming young toadfish 



in water mo 



CXIII. (13) Larval toadfish, showing formation of color bands and disappearance 



ofyolk mo 



Methods op studying the habits of fishes and recording their life histories; 



Plate CXIV. (i) Water glass designed for observation or photography of objects under 

 water. (2) Two-foot water glass supported on four legs and provided 



with screen, as used for studying and photographing lampreys 11 36 



CXV. (3) Reflecting water glass. (4) Male of common shiner, photographed in 



aquarium out of doors 1 136 



CXVI. (5) Photograph of nest of black bass, taken with aid of screen, camera 

 above water. (6) Brook lampreys on nest, photographed through 



water glass in running water 1 136 



1 CXVII. (7) Galvanized iron box with plate-glass front, designed to contain camera 



when used under water. (8) Photograph showing method of using 

 reflecting camera when inclosed in water-tight box for subaquatic 



work 1 136 



CXVIII. (9) Photograph of nest of a horned dace, taken with reflecting camera and 

 by aid of a cloth screen. (10) Male and two females of horned dace, 

 photographed in aquarium out of doors 1 136 



