100 Wisconsin Academy of Sciences, Aois, cmd Letters. 



I submitted tlie minute crustaceans to Dr. Stimpson, wlio 

 detected three species of fresh water shrimps, belonging to the 

 genus gammarius, and one species of mysis, a marine genus, 

 many species of which are found in the Northern Atlantic and 

 Arctic oceans. The small shell found with the crustaceans, in 

 the stomachs of the white-fish, proved to be an undescribed 

 species of pisidium. 



These discoveries were considered of sufhcient importance 

 to Justify the undertaking of a dredging expedition. Profess- 

 ors Stimpson and Andrews, with Mr. Blatcliford, of Chicago, 

 represented the Chicago Academy of Science, while Drs. Lap- 

 ham and Hoy represented the Wisconsin Academy of Arts 

 and Letters. 



_0n the 24th of June, 1870, we steamed into the lake, out of 

 sight of land, and spent the entire day in dredging in a most 

 enjoyable, and to science profitable, manner. We procured 

 living specimens of those crustaceans which I had previously 

 obtained from the stomachs of white-fish. But, with every 

 exertion, we were not able to keep them alive above a few 

 hours. Fitted, as they are, to sustain the great pressure of from 

 fifty to seventy fathoms of water, when this was taken off death 

 was the inevitable result. 



I here subjoin a catalogue of all the animals thus far known 

 to inhabit the deep water off Racine : 



Salmo amethystus — Mitchel 

 Coregonus sapidissimus — Agassiz. 

 Coregonus lattor — Agassiz. 

 Argyrosomus Hoyi — Gill. 

 Argyrosomus nigiipinnis — Gill. 

 Triglopsis Thompsonii — Girard, 

 Gammarius Hoyi — Stimpson. 

 Gammarius brevistilus — Stimpson. 

 Gammarius filicornis — Stimpson. 

 Mysis diluvianus — Stimpson. 

 Pisidium abysomus — Stimpson. 



