754 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



teen females and eight males; in two of the females, the eggs were 

 entirely undeveloped, and the same was the case with the milt in one 

 male fish, while in the others the sexual organs were fully developed. The 

 fins in these three fish were likewise much less developed, and the char- 

 acteristic modification of the skin found in the trout during the spawning- 

 season was wanting; in short, I recognized in these the barren variety 

 of the trout. As Siebold 1 has proved with absolute certainty the exist- 

 ence of such barren varieties, and has accurately described their char- 

 acteristic distinguishing marks, I will not enter further on this matter, 

 but will only remark that since I have continually found specimens of 

 barren trout. I will here add that there is no difference between barren 

 and fruitful trout with regard to their food. 



The section of the digestive organs showed immediately that their char- 

 acter was entirely different from those of Trutta solar and Trutta trutta. 

 The oesophagus and stomach were not contracted, but in most cases 

 considerably extended and showed symptoms of a — for the spawning- 

 season — very considerable feeding activity. Nearly all the organs 

 which play a part in digestion, from the oesophagus down to the anus, 

 contained remnants of food. Among the twenty-two which I examined 

 1 only found one whose digestive organs contained no remnants of food 

 whatever. Among the others there were several whose stomach con- 

 tained no food-substance, but in the entrails I found the indigestible 

 remnants of food. 



I will now briefly state what I found in these twenty-one trout: 2 



1. Twenty-one wings of insects (mostly neuroptera). 



2. Twenty-six parts of integuments, heads and wings of coleoptera and 

 orthoptera, as well as crustaceans and myriopods. 



3. Thirty-five tarsi and other portions of the legs of the same insects. 



4. Twenty-six larvae of Pkryganidce or their cases, composed of parti- 

 cles of quartz and plants. 



What I looked for most eagerly — viz, remnants of fish — I did not find 

 in any of these twenty-one trout. The stomach occasionally contained 

 large connected parts of insects, and in some stomachs I found the toler- 

 ably well preserved larvae of Sialis lutaria. On one occasion, I found six 

 cases of Phryganidm in a fish, and several times three or four were 

 packed closely together, so that they extended the stomach and could 

 be seen from outside. In some cases, the larvae of these cases were well- 

 preserved. I found no lime in these cases, and in bringing them in con- 

 tact with muriatic acid they did not effervesce. It was surprising to me 

 that in three fishes I found large portions of the bast of a plant (perhaps 



1 Siebold, op. cifc., p. 233. 



3 Any one occupied with similar observations will know that in most cases it is 

 almost impossible to draw any conclusion, as to genus and species of the animals which 

 have been devoured, from the half-digested and torn fragments which are found. 

 Although in most cases the accurate definition of these animals is of no practical value, 

 it is of great interest to the zoologist to get as near the truth as possible. I have, 

 therefore, attempted a definition wherever it was possible. 



