LAMPREYS IN CAPTIVITY. 



ALBERT M. REESE. 



HAVING had living lampreys of various ages under observa- 

 tion in the biological laboratory of Johns Hopkins University, 

 I present the following facts as to the ability of these animals 

 to live in a very limited space. 



I received, about the middle of May, from Ithaca, N. Y., 

 two lots of lamprey eggs, about six dozen eggs in each lot. 

 They were shipped by express and must have been on the road 

 about twenty to twenty-four hours. They had been shoveled 

 out of the "nest," with about 2 1. of gravel, and put into 

 two tin buckets of 8 1. capacity. The space in the buckets 

 above the gravel was filled with water, and in one of the buck- 

 ets were some three dozen larval lampreys ranging from 2 cm. 

 to 12 cm. in length. None of these eggs developed, although 

 they were put into running water as soon as they reached the 

 laboratory. 



My experience with the small larvae (about 5 mm. in length) 

 was more successful. I obtained one hundred or more of these 

 from a stream at Ithaca, and brought them to Baltimore in two 

 glass jars of 3-4 1. capacity each. A small quantity of gravel 

 was placed in the bottom of each jar for the larvae to bury 

 themselves in, and the water was kept cool by partially empty- 

 ing the jars from time to time, and refilling them with ice 

 water from the coolers on the train. The journey lasted for 

 about eighteen hours, and all the larvae, except three or four, 

 reached the laboratory in good condition. 



The small amount of sediment in the city water proving dis- 

 astrous to the welfare of the larvae, clear spring water was 

 obtained every few days, and this was kept cool by allowing 

 the jars to stand in larger vessels of running water. Even 

 with this arrangement the deaths averaged one per day, and 

 about the first of August the remaining larvae were killed and 



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