ILLUSTRATIONS 



PLATES 



New Diptera, or Two-winged Flies, from America, Asia, 

 AND Java, with Additional Notes 



By J. M. Aldrich 



Facing Page 

 1. Dyscrasis Sind Collinellula, new genera 28 



A Newly Discovered West Indian Mollusk Faunula 



By Paul Bartsch 



1-3. New West Indian mollusks 12 



The Forms of the Common Old World Swallowtail Butter- 

 fly (Papilio machaon) in North America, with Descriptions 

 OF Two New Subspecies 



By Austin H. Clark 



1. Papilio machaon sikkimensis 15 



2. Papilio machaon aliaska 15 



3. Papilio machaon hudsonianus 15 



4. Papilio machaon petersii 15 



5. Papilio machaon aliaska and P. m. petersii 15 



6. Undersides of specimens shown on Plate 6 15 



7. Papilio machaon aliaska 15 



8. Undersides of specimens shown on Plate 7 15 



On a Newly Mounted Skeleton of Diplodocus in the United 

 States National Museum 



By Charles W. Gilmore 



4 



1. Dinosaur National Monument 



2. Dinosaur National Monument and Dinosaur National Monument 



quarry 



3. Dinosaur National Monument quarry 4 



4. The Diplodocus skeleton as it was partly uncovered in the face of the 



quarry 5 



5. Skeleton of Diplodocus longus Marsh as exhibited in the hall of verte- 



brate paleontology in the United States National Museum 8 



6. Comparative views of the mounted skeletons of Diplodocus carnegii 



and D. longus 9 



VI 



