ZOOLOGY / 301

ZY 545-PHYSIOLOGICAL GENETICS. 4 credits
ZY 551-CYTOLOGY. 5 credits
ZY 570-CELLULAR PHYSIOLOGY. 5 credits
ZY 571-TECHNIQUES IN CELLULAR PHYSIOLOGY. 1 credit
ZY 574-ANIMAL PHYSIOLOGY. 5 credits
ZY 579-THE BIOLOGY OF MARINE ANIMALS. 4 credits

 GRADUATE COURSES
ZY 605-TROPICAL BIOLOGY: AN ECOLOGICAL APPROACH. 12 credits
 Identical with BLY 605, BTY 605. Field study of ecological concepts in tropical
environments. Offered summer quarters in Costa Rica as part of the program of the
Organization for Tropical Studies.
ZY 607-ANCIENT VERTEBRATE FAUNAS. 4 credits
 Identical with GY 607. Prerequisite: ZY 507 or GY 507. Evolution, distribu-
tion, and extinction of vertebrate faunas with emphasis on problems in paleoecology,
paleogeography, and patterns of phylogeny.
ZY 608-SEMINAR IN EVOLUTION. 4 credits
 Identical with GY 608. Processes, mechanisms, patterns, and orientation of
 evolution.
 ZY 609-ZOOGEOGRAPHY. 3 credits
 ZY 610-ADVANCED TROPICAL ZOOLOGY. 12 credits
 Identical with BLY 610. Vertebrate or invertebrate group selected as basis for
studies of ecological systems in the tropics. Effects of elevation and temperatures
on populations, successions, microhabitat, distribution, predation, evolution, and
other aspects. Offered winter and summer quarters in Costa Rica as part of the
program of the Organization for Tropical Studies.
ZY 612-MARINE ECOLOGY. 5 credits
 Prerequisites: ZY 308, CY 213 or equivalent. Marine communities and the
 physical and chemical factors that influence them.
 ZY 624-HELMINTHOLOGY. 5 credits
 Identical with VY 624. Prerequisite: ZY 516. Physiology, biochemistry, life
 cycles, and morphology of the helminths. The host-parasite relationship and immune
 responses.
 ZY 625-PROTOZOOLOGY. 5 credits
 Identical with VY 625.
 ZY 626-COMMUNITY ECOLOGY. 5 credits
 Prerequisite: ZY 505. Selected animal habitats, their occupants and organiza-
 tion. Classroom work evaluates community concept and appraises role of ecology
 in evolution.
 ZY 628-LIMNOLOGY. 5 credits
 Prerequisites: ZY 505, BTY 380, CY 213. Biological, chemical, and physical
 dynamics of inland waters.
 ZY 629-SEMINAR IN ECOLOGY. 2 credits
 Prerequisites: ZY 505, ZY 626. May be repeated with change of content up to a
 maximum of 6 credits.
 ZY 630-INDIVIDUAL STUDIES IN ZOOLOGY. 4 credits
 Studies selected from the following fields: comparative anatomy, cytology, ecol-
 ogy, embryology, fresh water biology, genetics, herpetology, histology, icthyol-
 ogy, invertebrate zoology, including arachnology and insect biology, limnology,