I SO H. H. NEWMAN. 



species taken in April and in May showed, in certain regions, but 

 one contact organ to the scale. From the center they are pro- 

 duced outward in both directions. A common condition observed 

 in specimens of F. Jieteroclitus taken in May was that of one rather 

 large organ in the middle of the free edge, flanked on each side 

 of the center by a small organ. There is abundant evidence that 

 other organs may later be intercalated between those first formed. 



The contact organs disappear for the season in about six to 

 eight weeks after the close of the spawning season. Specimens 

 collected early in September showed only the faintest traces of 

 the organs. Evidently, judging by appearances of these vestiges, 

 they are partly worn off by friction and partly resorbed. They 

 leave a permanent record of themselves in the angularly wavy 

 outline of the newest osseous ring of the scales. No such trace 

 seems to be left on the fin rays. 



Function. Two possible functions might be subserved by the 

 contact organs, that of frictional surface on the parts of the body 

 of the male with which he holds the female in spawning, and that 

 of contact sensation. That the former function is well subserved 

 is evidenced by the roughness that one notes with the fingers 

 wherever the contact organs are well developed and numerous, 

 and by the fact that the male is actually able to hold the female 

 quite firmly for several seconds. The fighting males are able to 

 inflict any real injury upon one another by means of the contact 

 organs is highly improbable, although they strike one another 

 fiercely with parts well armed with the latter. That scales and 

 fins are decidedly sensitive to contact is well known. Micro- 

 scopic examination of these parts, prepared by special neurolog- 

 ical methods, failed to show that the contact organs were any 

 more richly enervated than the rest of the free edge of the scale 

 or the general surface of the fin. It is probably true, however, 

 that the projecting position of the contact organs renders them 

 more subject to contact sensation than the surrounding flat 

 regions of scales and fins. 



