514 DB. H. VON IHEEING ON THE [-^pr. 18, 



Hemitriccus, Heliobletus, Batora, Phihalvra, Stephanophorus, 

 Hypophaa, Orthogoni/s, Lencochhris, and Tridaria ; and (b) Cni- 

 polegus, Cyhernetes, Alectrurus, Cyanotis, Fhlceocryptes, Anumhiiis, 

 and Coryplwspiza. 



The first group includes what are essentially South Brazilian 

 genera ; the second those of Argentina, which, advancing north, 

 enter Southern Brazil. Many of the Argentine species occur in 

 Sao Paulo at Itarare and Eio Verde only, on the boundary of the 

 State of Parana. To these it will be convenient to add some 

 other species not yet observed in Sao Paulo, such as Tanioptera 

 doniinicana Vieill., Piprites pilenhts (Temm.), Leptasthenura striolata 

 Pelz., Siptornis ruticilJa (Licht.), Phacellodomus striaiicollis (Lafr. 

 & d'Orb.), and Clihanomis dendrocolaptoides (Pelz.). 



It is a fact of zoo-geographical interest, that the boundary 

 between Sao Paulo and Parana corresponds to a faunistic line 

 which is not transgressed by many birds characteristic of the 

 Argentine Pampas. 



Of special interest is the occurrence of Cyanotis azartp and 

 PhJceocryptes wielanops — typical Patagonian birds which are likewise 

 found in Chili, Eio Grande do Sul, and Bolivia. We have received 

 from Iguape not only these birds but also their nests. These tw^o 

 birds accompany each other and occur in reedy swamps. It may be 

 that they are resident at Igua])e only in the summer ; but it is also 

 possible that they have been resident there since the time when the 

 coast extended more to the east, and lowlands with marshes and 

 lagoons occupied that part of the ocean which connects Eio Grande 

 with Iguape. 



AVe have many singular facts which tend to this conclusion. Azara 

 lahiaia and Paludestrina are brackish-water species of mollusks, 

 common from Iguape to Buenos Ayres; and again, Chilina Jimninea 

 and Glaharis exotica, of the fresh-waters of Iguape, are species 

 characteristic of Eio Grande do Sul and Argentina, which are 

 not found at all in the centi'al and northern parts of the State of 

 Sao Paulo (see my papers on the Geographical Distribution of the 

 Freshwater Fauna of Southern Brazil). I cannot accept the 

 explanations given by Dr. Ortmann, who says that the Potamoniidce 

 do not coexist with the Parcistaddce because of the effects of 

 the struggle for life. Iti Eio Grande do Sul they do coexist, and 

 I have obser\ ed that they cannot ei^ter in competition, since they 

 are quite different in their mode of life. The only satisfactory 

 explanation is that based upon terrestrial modifications, as 

 suggested above ; and it seems to me that Cyanotis and Phloeo- 

 cryptes, had fliers as they are, must be considered, from the same 

 point of view, as being relicts. 



Cygnus melanocoryphus sometimes appears on the coast near 

 Iguape. A curious fact is the appearance of a Penguin, 

 SpheniscKs magellanicus, on the coasts of Parana and Sao Paulo. 

 I am informed that last winter, during July and August 1898, 

 thousands of dead Penguins were observed there. We have received 



