XIV LIST OF ILLUSTRATION'S 



Pago 



20. Superficial musculature of the lateral aspect of the left anterior limb 



of Zalophus 68 



21. Superficial musculature of the lateral aspect of the left anterior limb 



of Phoca hispida 69 



22. Superficial musculature of the medial aspect of the left anterior limb 



of Zalophus 72 



23. Superficial musculature of the medial aspect of the left anterior limb 



of Phoca hispida 73 



24. Ventral aspect of the muscles extending from the innominate bone 



(stippled) to the posterior limb of Zalophus (Z) and Phoca his- 

 pida (P) 83 



25. Cranio-lateral aspect of the superficial muscles of the left posterior 



limb of Zalophus 90 



26. Cranio-lateral aspect of the superficial muscles of the left posterior 



limb of Phoca hispida 91 



27. Caudal aspect of the musculature of the left posterior limb of Zalophus^ 98 



28. Caudal aspect of the musculature of the left posterior limb of Phoca 



hispida 99 



29. Position assumed by Mirounga illustrating possible degree of vertebral 



bending 121 



30. Diagram illustrating approximate static posture (solid lines) and 



degree of possible movement (broken lines) in life of each jointed 

 segment of the posterior limbs of Zalophus (Z) and Phoca hispida 

 (P). I, innominate; T, thigh; S, shank; H, heel (Astragalus and 

 Calcaneum) ; and F, remainder of foot 125 



Zeolites from Ritter Hot Spring, Grant County, Oregon 



By D. F. Hewett, Earl V, Shannon, and Forest A. Gonyer 



1. Sketch map of Ritter Hot Spring area. Grant County, Oreg 3 



The Florida tree snails of the genus Liguus 



By Charles Torrey Simpson 



1. Diagram illustrating the distribution and migration of Liguus in 

 Florida. The open spaces are pine woods; those inclosed in lines, 

 hammocks. Dotted lines show migration to and from hammocks. 

 Some bits of forest are reached by several; others are entirely 

 missed 18 



Tertiary fossil plants from the Argentine Republic 



By Edward W. Berry 



1. Localities in Lago Nahuel Huapi region, Rio Negro territory; 2. Locali- 

 ty of Mirhoja, Chubut territory; 3. Localities in Rio Chalia 

 region, Santa Cruz territory 2 



Notes on American two-winged flies of the family Sapro- 



MYZIDAE 



By J. R. Malloch 



1-2. 1. Head of Asilostoma palpalis from side. 2. Wing of A. palpalis-. 5 



3-4. 3. Wing of Asilostoma pallipes. 4. Head of A. pallipes from side__ 6 



5. Head of Freyia mgrila irom side 9 



