INDEX TO VOLUME IV. 
Page numbers italicized indicate the most important entry under the heading. The numbers 
with asterisks refer to text illustrations. Synonyms are in italics. 
y^BDERITES, 417, 418, 43 s , 442, 443 
altiramis, 452 
crasignathus , 439 
crassignathus, 438, 439, *440 
cr as sir amis , 439 
meridionalis, 439, 442, 451 
serratus, 45 1 
tenuissimus, 452 
Abderitidce , 416 
Abderitinae, 4/7, 4.38, 442, 443 
Acdestis, 434, 452 
elatus, 452 
oweni, 452 
parvus, 453 
Acmsea, 16 1 
heroldi, forma pygmaea, 161 
Actaeon, 34, 243 
chilensis, 243 , 257, 304 
semilaevis, 244, 258, 273, 294, 295 
semistriatus, 245, 294 
subscalatus, 244 
tornatilis, 244 
turgidus, 244, 304 
Actaeonidae, 243 
Acrobates pygmaeus, 336 
Acrocyon, 445 
equianus, 445 
patagonensis, 445 
sectorius, 445 
Acyon, 449 
bardus , 446 
tricuspidatus, 449 
Acyonidce, 339 
Africa, connection with Antarctica, 3 1 6 
Africa, South, 12 
Agassiz, A., 54, 56, 60 
L., 59, 60 
Agustylus, 446 
bardus, 446, 447 
carnifex, 446 
cynoides, 446 
primaevus, 446 
Allen, J. A., 334 
Amathusia, 134, 133 
angulata, 134, 257, 262, 266, 268, 270, 
271, 282, 283, 298 
Ameghino, F., 7, 79, 103, 104, 262, 265, 266, 
267, 268, 269, 270, 271, 273, 274, 275, 
276, 279, 280, 282, 284, 285, 287, 288, 
303, 308, 309, 333, 334, 335, 339, 343, 
348, 352, 378, 407, 408, 412, 416, 418, 
419, 426, 429, 430, 431, 434, 435, 436, 
437, 439, 442, 443, 444 
America, North, 333, 444 
South, 11, 333, 339 
connection of, with Antarctica, 314 
with Australia, 444 
Cretaceous of, 6 
Ammonite beds, see Belgrano beds 
Ammonites cleon , 36 
clypeformis , 37, 38 
leopoldinus, 37 
sp., 8 
telinga , 37 
Ammonites, 7, 9, 10 
Patagonian, 38 
Amphiproviverra, 340, 343, 344, 345, 346, 
356, 363, 365, 370, 376, 378, 380, 
385 ,394, 407, 408, 412 
461 
