Plate 77 



Figure 1. Pisaster giganleus; section ou1 of actinal area, viewed from aboral end to show actinal 

 and inferomarginal spines; medium-sized specimen from Monterey, X10. a, a, n, 

 : i « • t i 1 1 ; 1 1 plates; a<l, adambulacral; am, lower end of ambulacra] ossicle; x, super- 

 actinal buttress mentioned in text, and side of one of the superactinal fenestrated 

 pits. 



2, 2a, 26. Pisasier giganieus, type; three abactinal spines 2.7 3 mm. long, 10. 



3. Pisastt r giganteus, Monterey Bay; three abactinal spines, 1.6 mm. long, X 10. 

 3o. Same; an abactinal spine from a medium-sized specimen, X25. 



'Ah, 3c. Sana-; actinal and inferomarginal spines, same specimen as .':'. and 3a, X10. 

 I. Pisaster giganteus capitatus, Laguna Beach, Calif.; two abactinal spines, 2.8 mm., X10. 



4a. Same s] imen; an inferomarginal spine, X10. 



5. Pisaster giganteus, Monterey Bay; three clusters of abactinal papulae drawn from a 



rather smaller than medium-sized live specimen, X6. 

 G. Pisaster giganleus; pedicellaria from actinal interradial channel, same specimen as 3 and 5, 



X25. 

 6a. Same specimen, from intermarginal channel, 1.2 mm., X25. 

 6b. Large specimen from Monterey; an intermarginal stone-hammer pedicellaria, 1.2 mm., 



X25. 

 tic. Same specimen as (in, inside of a valve or jaw. 

 Sd. Type of P. giganteus; an abactinal pedicellaria, 1.12 mm., X10. 

 7. Pisaster giganteus; month plates and inner part of adoral carina of a medium-sized 



Monterey example, showing distorted development of first few adambulacral 



plates, X8. This is from a dry specimen and the prominent festoons of straight 



pedicellariae are indicated without detail. 



7n. Actinostomial spine <'f another specimen. 

 332 



