126 FI.SHES FROM GUAYMAS tVERMANN AND JENKINS. 



of moisture over the northern hemisphere is sufficient to make one 

 hesitate before committinj:^ himself unreservedly to any other theory; 

 at any rat*;, to one which has not for itself indeijendent and adequate 

 proof.*' 



In the Appendix to the same volume, Mr. Warren L'pham, in dis- 

 cn.s.sing the probable causes of glaciation, says: "The (Quaternary up- 

 lifts of the Andes and Kocky Mountains and of the West Indies make 

 it nearly certain that the Isthmus of Panama has been similarly ele- 

 vated during the recent epoch. * * * It may be true, therefore, 

 tliat the submergence of this isthmus was one of the causes of the 

 Glacial period, the continuation of the erjuatorial oceanic current west- 

 war<i into the Pacific having greatly diminished or wholly diverted the 

 Gulf Stream, which carries warmth from the tropics to the northern 

 Atlantic and northwestern Europe.'' 



A113' very recent means by which the fishes could have passed readily 

 froju one .side to the other would have resulted in njakingthe fish faunae 

 of the two shores practically identical ; but the time that has elapsed 

 .since such a water way couhl have existed has been long enough to 

 allow the fishes of the two sides to become prncticoUij diatinct. That 

 the molluscs of the two shores are also almost wholly distinct, as shown 

 by Dr. Pischer, is even stronger evidence of the remoteness of the 

 time when the means of communication between the two oceans (•j)n]d 

 have existed, for "species" among molluscs are jjiobably more persist- 

 ent than among fishes. 



Uur present knowledge, therefore, of the fishes of tropical America 

 justifies ns in regarding the fi.->h faun;e of the two coasts as being essen- 

 tially distinct, and that there has not been, at any conifjaratively recent 

 time, any water way through the Isthmus of Panama. 



We are under great obligations to the Mexican minister at Washing- 

 ton, Senor Komero, aud to other officials of the Mexican Government, 

 for valuable assistanf^j and for many (^jurtesies extended to us; also to 

 lion. A. Willard, United States c^^usul a1 Guaymas, who rendered us 

 valuable aid in mani' ways; and to Dr. David S. Jordan, president of 

 Indiana University, wewi.sh to acknowledge our great indebtedness for 

 the use of his valuable library and extensive ryjllections. 



The following is a list of the twenty-one si>ecies described as new to 

 science: 



1. Khirioptera Kteiudacbneri. | 12. Gobina cfaiqnita. 



'J. 8jur>dn«jeukinHi .Jordan dL I>;11 mail. J 13. OobiuH UjugicandaH, 



3- 8if»Iio^toma arctuio. 



4. >leijidia c\;iTa. 



h. M(;tiidia nardina. 



G. Alherinojw r«gi». 



7. C»^rjtrof»ornn» ^andocnlattis. 



H. MycOTOfM rca jordaui. 



9. HennoMilla a^nrea. 



10. Uy>erjeii» rathbntii. . 21, Citbariclitbya gilberli 



11. Fi^eadojulia veituotuM. \ 



14. GillicbtbyM j-caiida. 

 L5. Gilhcbtbyh ^uaymawi 



16. Scorpa;ria wjuora;. 



17. GnatbyiKipB hcoj*. 

 XH. OjijfjthogDatbiJHs oniMiala. 

 ly. A»icbfer)oj»f>'ruh nf-imr. 

 20. PnediifA^letiriitiH bypacautbuH. 



