No. 5. 
No. 6. 
No. 7. 
No. 8. 
Index 
PAGE 
Non-Inerusting Chilostomatous Bryozoa of the West Coast 
of North America, by Alice Robertson. With 2 figures 
and Plates, 4-16) x. -.sccxsscecen sci cce soe eee ce eee 235-322 
Tintin tn GLO 25 saeco neck ee ee 230-237 
Mer marnOlO gy cease oekcc lees Ro a Sa ee eee ee 237-241 
Tiist o£ (Spectes j2::cc.csces lai -ccks eee 241 
Description) jof Species! 5.2 eet cen eee eee bates nate nae 242-292 
Bibliogranpbyy ¢ 22.2 b sooo cck LESS ee ose caer eee ee mre oe 293-296 
Deseription: of Plates: a2 .2c.cc ceases eee one en ee 297-322 
Differentiation in Hydroid Colonies and the Problem of 
Senescence, by Harry Beal Torrey. With 4 figures -...... 323-332 
Observations See cse ee eee ee eee ere ee RR oN 323-331 
General, consid eratioms) ooo ease eee 331-332 
The Behavior of Corymorpha, by Harry Beal Torrey. With 
PAL OUP OSs) sees eee ee peat eh ae SESS A See Pe ad oe Ek ee 333-340 
Dinoflagellata of the San Diego Region, I. On Hetero- 
dinium, a new Genus of the Peridinide, by Charles 
Atwood ‘Kotoid:* (Plates ilo oe eect ee 341-368 
Introduction and Acknowledgments ..........-....------.-2-------200--00 341 
Deseription of Genus Hleterodimium —-..2 222.222 ees 341-342 
Detailed Description of generic Characters .....................-.....- 342-351 
Synoptic Key to Species of Heterodinium .............................- 350 
Discussion of Species -......... Sh i es ee 301 
Biblio praplyy. » co ewcse ss ee acasn ance ce eae nae eee 363 
Description of Plates -......... DR a Ee ORs ast A oc nd 364-368 
pgs tS ee ee ee ee ae ete ea Ae, COL als 
