174 The Ohio Journal of Science [Vol. XXI, No. 5, 



Lycosa sp. One immature specimen of this genus was found. 

 Although there is one species aquatic in the manner of D. scxpunctatus 

 it is not found in this region, and the one taken was undoubtedly a 

 terrestrial one. 



Pardosa nigropalpus Emerton. This, an inhabitant of moist places, 

 was found on vegetation above water at a number of stations, but is 

 not to be regarded as aquatic. 



Phylum CHORDATA. 

 Subphylum VERTEBRATA. 



It is not known what fishes were in the creek that flowed 

 through the ravine in the early days, nor just w^hat kinds and 

 when fishes w^ere introduced into Mirror Lake, but that some 

 were introduced before the draining of 1895 and several times 

 subsequently is certain. In 1898 (Osburn '99) a spring freshet 

 carried many down to the Olentangy. These points are worthy 

 of note because the fishes, at least to a relatively far greater 

 extent than any other forms, owe their existence in the pond, 

 to artificial introduction. They established themselves firmly, 

 and so altered conditions in the large pond, as to be the dom- 

 inant organisms there. 



In the small pond very few fishes were found. Before con- 

 nection of the large wdth it (April, 1919) they w^ere rare there as 

 far as could be ascertained without seining. The union gave 

 opportunity for migration. Though none were observed moving 

 from the large pond, through the narrow^ channel into the small, 

 some fishes w^ere seen in the latter in the fall of 1919, and 

 decidedly more in the spring of 1920.* 



No study of fish food was undertaken. Hence it is only on 

 general principles, but substantiated by deductions from com- 

 parisons between the two ponds, that it can be said that the 

 absence of many forms of life in the large pond, could be 

 attributed to the fishes. The large pond was probably over- 

 inhabited as far as fishes are concerned. The supply of natural 

 food W'as added to at times by throwing in broken bread, 

 .usually in the vicinity of station 4. The goldfish took to this 

 food more readily than others. 



All fishes were collected in two seinings (September 27 and 

 October 4), by Mr. Wickliff and the writer. 



* The interesting study of the effects in cotirse of time, of increasing numbers 

 of fishes in the small "pond, oii the fauna' there, can never be made, since the small 

 pond was done away with, June, 1920. ■'- " ' ^ .' . 



