24 BULLETIN OF THE UNITED STATES FISH COMMISSION. 



come back to them a^ain tliinkiug they could get back to the streams 

 to spawn where they spent their chiklhood days, but the leaps are too 

 much for them. There never were any salmon caught in the Genesee 

 before last year. I have fished the river for fifty years. I do not know 

 whether they were California or Kennebec salmon; I did not see them. 

 The fishermen think we do not want them caught, and have kept shy of 

 me. I have spent some days on the river since to let them know that 

 we did want them caught in the spring of the year, and to let me know 

 if they catch any more. 



NOTES OIV THE DEVEI^OPMENT, SPIIVIVIIVCJ HABITS, AND STRUC- 

 TURE OF THE FOUR-SPIIVEO STICKI^ERAC'K, APEr.TES QUADRA- 



cus. 



BY JOHI¥ A. RYDER. 



Nests and ova of this species were recently brought to me for investi- 

 gation by Mr. W. P. Seal, who obtained them in the ditches along the 

 Delaware, below Philadelphia. More recently (April 27), the same gen- 

 tleman had the kindness to bring me a pair of adults about to spawn, 

 the male very industriously completing the nest under my observation 

 in an aquarium extemi)orized for the purj)ose. 



The early stages of development I did not witness, as the first lot of 

 eggs had the blastoderm already formed, and inclosing tbe vitellus, and 

 those laid by the pair in confinement were unluckily not impregnated. 

 The egg-membrane is a true zona radiata, being perforated by numerous 

 pore canals, and is covered by an adhesive material, which aggluti- 

 nates the eggs together into a mass to the number of 15 to 20, the number 

 laid at one time. The ova sink to the bottom, and must be taken charge 

 of by the male, as the female after having ridden herself of them takes 

 no farther interest in their welfare. They measure one-twelfth of an 

 inch in diameter, and are of an amber color. I was not able to discover 

 a micropyle, but believe that one exists, nevertheless ; at one pole of the 

 egg a large number of button-shaped appendages are attached to the 

 surface of the egg-membrane by means of i^edicels, and it is in the midst 

 of these that the micropyle is found in the European species, Gaster- 

 osteus leiurus, according to Ransom. 



Kot having witnessed the early stages of development, I will only 

 describe the structure of the ovum. There is no germinal disk developed 

 when the egg first leaves the ovary, and the germinal layer is uniformly 

 distributed as a thin uniform granular envelope, inclosing the clearer 

 vitelline i^rotoplasm, which itself incloses a number of very refringent 

 oil spheres of very variable size. Later, it appears that a germinal disk 

 is developed without the influence of impregnation. 



The formation of the. segmentation cavity I have not witnessed, but 

 I have a belief that it is present, inasmuch as there is a space developed 



