LIST OF CONTRIBUTORS. 107 



Leidy, Joseph. ( 'onti/nui d. 



Mastodon andmm. P '76, 38 



Remarks on Arcella, etc. P '7(5, 54 



On fossils from the Ashley phosphate beds. P '76, 80, 86 



Fish remains of the Mesozoic red shale. P '76, 81 



On vertebrate fossils from the phosphate beds of South 



Carolina. P '76, 114 



On the rhizopod genus Nebela. P '76, 115 



Bituminous sediment of the Schuylkill River. P '76, 193 



On the structure of precious opal. P '76, 195 



— — Observations on rhizopods. P '76, 197 



On Hyraceum. P 76, 325 



On ozocerite. P 76, 325 



On itacolumite. P 766, 326 



Impurities in drinking-water. P 77. 20 



On Eozoon. P 77, 20 



On the diaphragm. P 77, 20 



On the yellow ant. P 77, 145 



On intestinal parasites of Termes flavipes. P 77, 146 



On gregarines. P 77, 196 



On Chilomonas. P 77, 198 



On flukes infesting mollusks. P 77, 200 



— ■ — On some parasitic Infusoria. P 77, 259 



On the seventeen-year locust, the hessian fly and a chelifer. 



P 77, 260 



The birth of a rhizopod. P 77, 261 



■ On the bed-bug and its allies. P 77, 284 



— - On the feeding of Dinamoeba. P 77, 288 



Concretions resembling bones. P 77, 290 



■ Apparent discriminative power in the selection of food by a 



helizoon. P 77, 291 



Remarks on rhizopods, and notice of a new form. P 77, 293 



On fossil fishes. P 77, 294 



Remarks on ants. P 77, 304 



Remarks on the American species of Difflugia. P 77, 306 



Circumspection of ants. P 77, 320 



Rhizopods in an apple tree. P 77, 321 



On citrine or yellow quartz. P 78, 40 



On Amoeba. P 78, 99 



A hippopotamus tusk. P 78, 99 



A louse of the pelican. P 78, 100 



