058 MR. W. p. PYCRAFT ON THE [DeC. 13, 



Fig. 3. Pcriplaneta americana, p. Q'db. 4-jointed reproduction form of tarsas 

 (from third pair of legs). X 8. 



4. Stylopyga orientalis, p. 939. Malformed tarsus, 3rd pair, nyinph. a', 



a"', incomplete articulations ; a", a'*', complete 

 artioulationa. 



5. „ „ Malformed tarsus, 3rd pair, nymph, a', a'", 



comjjlete articulations; a", incomplete articu- 

 lation. 



6. „ „ Malformed tarsus, 3rd pair, $ adult. 



7. ,, „ Malformed tarsus, 1st pair, nymph. 



8. „ ,, Malformed tarsus, 1st pair, cj' adult. 



9. „ „ Malformed tarsus, 2ud pair, J adult. 

 10. „ ,, Malformed tarsus, 2nd pair, nymph. 



[Figs. 4 to 10 are not to uniform scale.] 



2. Contributions to the Osteology of Birds. 

 Part II. Lnpennes^. By W. P. Pycraft, A.L.S. 



[Reeeived October 24, 1898.] 

 (Plates LIX.-LXT.) 



Contexts. 



i. Introductory Eemarks, p. 958. 

 ii. The Skull of the Adult, p. 959. 

 iii. The Skull of the ^'estling, p. 967. 

 iv. The Vertebral Column, p. 976. 



T. The Pectoral Girdle and Sternum, p. 977. 

 Ti. The Pelvic Girdle, p. 978. 

 vii. The Pectoral Limb, p. 979. 

 viii. The Pelvic Limb, p. 980. 

 ix. Summary, p. 981. 



X. Key to the Osteology of the Inipennes, p. 932. 

 si. List of the principal Works referred to and consulted, p. 987. 



i. Introductory Eemarks. 



The Iinpennes represent one of the most sharply defined 

 groups to be found amongst the Cariuatae. The skeleton presents 

 many features which are quite unique. This is particularly the 

 case with regard to the shoulder-girdle and pectoral hmb, which 

 haA'e become considerably modified in adaptation to new func- 

 tions — the use of the fore limb as a paddle instead of as an 

 instrument of flight. The pectoral hmb, shoulder and pelvic 

 girdles have departed furthest from the typical Avian form ; they 

 represent the high-water mark of skeletal specialization \^hich has 

 been attained by the group, whilst the skull, pes, and thoracic 

 vertebrae represent the least specialized and most primitive portions 

 of the skeleton ; but they do not furnish us with any facts of very 

 great importauce, they do not carry us bej'ond the confines of the 

 Class. Osteologically the Penguins seem to be most nearly 

 related to the Tubinares and Pygopodes, and, as Dr. Gadow and 

 others have shown, the evidence of the soft parts confirms this 

 supposition. 



> For Part I., see P. Z. S. 1898, p. 82. 



