398 DR R. W. SHUFELDT. 



the epipleural processes in mid-series are of great size, with 

 paddle-shaped ends. There is one pair of long, sweeping, 

 pelvic ribs, but their haemapophyses do not quite reach the 

 costal border of the sternum upon either side. In A2')tenodytes 

 pcnnantii there is also a pair of ' floating costal ribs,' articulat- 

 ing with a pair of floating vertebral ribs, that are represented 

 simply by short, rod-like pieces. 



Among Penguins, the j'^e/vis exhibits a very considerable 

 amount of variation. It is long and narrow in Aptenodytes, and 

 relatively shorter and broader in Spheoiiscus, while in JEndyptes. 

 chrysocome and in JE. pachyrhynchus it seems to hold an inter- 

 mediate place in this respect. In all the pre-acetabular portion 

 of either ilium is a thin, plate-like, narrowish lamina of bone, 

 that simply rests upon the sacrum, and rarely co-ossifies com- 

 pletely with it, even in old birds. The inner iliac margins in 

 this region nowhere near approach the sacral crista, and the 

 anterior iliac margins may be once or twice notched, — twice 

 profoundly notched in a pelvis of Eudyptes pachyrhynchns at my 

 hand (No. 17,840 U.S. Nat. Mus.) ; while the pre-acetabular 

 part of ian ilium is placed horizontally, its post-acetabular part 

 lies in directly the opposite plane, or is vertically situated. The 

 acetabular region itself is more or less massive ; the anti-tro- 

 chanter not very large, but the cotyloid ring distinctly so. In 

 E. chi'ysocome the cotyloid ring is nearly double the size of the 

 ischiac foramen, and the proportion is even greater in Apte7W- 

 dytes, but in 8p)heniscus demersus the ischiac foramen is nearly 

 four times as big as the acetabular ring. In all Penguins 

 examined by me the postero-ilio-ischiac notch is well marked, 

 and the elliptical obturator foramen is continuous with the long 

 obturator space. The long blade-like pubic bone is not in con- 

 tact with the ischium above it, and rarely projects much beyond 

 the pelvis behind. In Spheniscus and Aidenodytes it is both 

 paddle-shaped and decurved posteriorly, but this is not the case 

 in Endyptes. This last-named genus has the upper margin of 

 the pubis nearly parallel to the lower margin of the ischium 

 above it, and the space dividing the two bones exceedingly 

 narrow, especially in E. clirysocome, but the two elen)ents do 

 not come in contact with each other. 



Seven free vertebrae are found iti the skeleton of the tail of 



