HO W. C. ALLEE. 



coverslip and by staining in methyl green or aqueous iodine, a 

 cell-agglutinating type of blood.-clott ; ng may be observed. 1 



Autotomy is usually demonstrated in Uca, the fiddler crab, by 

 crushing the distal end of one or more of the legs with a pair of 

 forceps. Chromatophore activity is well shown in Palcemonetes. 



Limulus. One day, lecture and laboratory. We formerly 

 gave a half day to the external anatomy of Limulus, using small 

 specimens. At present in addition to the time on the external 

 anatomy and feeding experiments, a half day that usually stretches 

 well on into the night is spent in dissection. Limulus is particu- 

 larly interesting to us as a persistent type, because of its use in 

 phylogenetic theory and because it is a characteristic and common 

 large invertebrate of Woods Hole. The dissection directions have 

 been worked out in the main by Dr. R. H. Bowen and are given 

 in full as Appendix VII, since I know of no other directions in 

 print. 



Mollusca. Five clays laboratory, four lectures. This group 

 is introduced by work on Chceto pleura, which may be mounted 

 on glass slides if put under water, and may then be readily studied 

 on both dorsal and ventral sides. The principal study of the group 

 centers about Venus (or Unio), Busycon and Loligo. Usually 

 one instructor is in charge of the earlier part of the work and an- 

 other has the Cephalopoda. 



In the Pelecypoda, comparative studies are made of Pecicn, 

 Mytilus, Mya, Ensis and Ostrca, with a drawing of one form ; and 

 living and preserved slides are studied in Venus, Mytilus and Os- 

 trea. The gill current can best be seen in the latter on account of 

 the large large size of the palps on which ciliary currents can be 

 seen. In the opening dissection, the blood system shows much 

 better if injected through the ventricles. 



The work in this group also includes study in locomotion of 

 Ensis, Yoldia, and Solcmya, and egg laying, fertilization and 

 cleavage in Cumingia. 



The gasteropod work is limited to Busycon (Sycotypns, 

 Fulgur}. These are killed and injected a week before using in 

 order that they may be hardened sufficiently to get rid of slime 



i Tait, Jour. Mar. Biol. Assn., 1911. 



