THE INVERTEBRATE COURSE. 113 



July 30, Saturday : 



North Falmouth Flats. Start 8:45; low tide, 9:35; re- 

 turn about 3 :oo. 

 August 4, Thursday : 



Kettle Cove, Rocks and Flats. Start 1 145 ; low tide, 2 :33 ; 



return about 5 :oo. 

 August 6, Saturday : 



Picnic. (1921, Penikese.) 



Practically the same field organization has been used for the 

 last eight years. The class is divided into as many teams as there 

 are instructors ; the team has the same members throughout the 

 course, but the instructors rotate so that each team has the benefit 

 of three different instructors in the field. In each team one 

 student is recorder for the day ; others have various assignments 

 depending on the trip. If this be to a flat, two have shovels, one a 

 bucket and crystallization dish, one a Cumin gia sieve, and the rest 

 carry collecting kits with bottles and jars, forceps and lenses. All 

 are mentally and physically prepared to get wet and dirty. 



The Protozoa field trip follows the Protozoa work in the lab- 

 oratory. While the class is studying Coelenterates and sponges, 

 two trips are made to wharf piles. Collecting is done from small 

 boats, and glass-bottomed buckets and scrape nets are an impor- 

 tant part of the equipment. The trips to flats and rock gutters, 

 and the dredging both depend for their sequence on the tides. It 

 is a general rule never to take a trip in the morning and attempt 

 regular class work in the afternoon. We have found that the 

 students are too tired or diverted to settle down to class dissec- 

 tion. They are interested in working over the specimens col- 

 lected on the trip and- this informal study has become more com- 

 mon of recent years. 



At the beginning of the course the student is supplied with a 

 check list of the animals taken by the class in the last ten years. 

 It is suggested but not required, that these be made the basis of 

 class records of experience for the season, so that the student ob- 

 tains a permanent record of the habitat distribution found by the 

 class collecting that year. 



The recorders are furnished with a board bearing a list of the 



