278 REPORTS ON INVESTIGATIONS AND PROJECTS. 



tentacles in Pocillopora. A paper on the first subject has been sub- 

 mitted for publication, and one on the second is nearly completed. 



Among the large number of dried coral collected are certain forms 

 very suitable for a study of variation by biometrical methods. Work 

 has already been begun upon two species and promises results of some 

 interest as regards the possible variations within a species. 



(b) Fossil Corals. — A contribution, "The Morphology of the 

 Madreporaria ; VI, The Fossula in Rugose Corals," has already been 

 published. The paper is a study of the rugose corals along develop- 

 mental lines, with the object of arriving at the nature of the fossula. 

 It is therein shown that the two lateral fossulse correspond with 

 development stages in the growth of the septa, while the cardinal 

 fossula is in addition probably to be associated with the presence in 

 the polyp of a siphonoglyph. From this support is gained for the 

 author's previous contention that the Rugosa are closely "elated to 

 the modern Zoanthid actinians. 



(c) Physiology of the Zoa?itharia. — While in the Hawaiian Islands 

 experiments and observations were made upon the living activities 

 of coral polyps, and the preparation for publication of the results has 

 been continued. A paper, "The Role of Mucus in Corals," is now 

 completed. The paper discusses the conditions under which mucus 

 is exuded and its importance as a protection to the polypal surface, 

 and also in the entanglement and ingestion of food substances. 



A second contribution, " The Habits and Reactions of Crabs Bear- 

 ing Actinians in their Claws," is almost completed for publication. 

 The paper is a result of observations and experiments conducted upon 

 the crab Melia tessellata, and discusses the mutual relationships of the 

 crab and its commensal actinians, the reactions of one toward the 

 other, the manner in which the combination is brought, and the pecu- 

 liarities which each exhibits in correlation with the commensal habit. 



Eigenmann, C. H. t Indiana University, Bloomington, Indiana. 

 Grant No. 68. Investigation o?i the blind fishes in the caves ot 

 Cuba. (For previous reports see Year Book No. 2, p. xlii, and 

 Year Book No. 3, p. 138.) $1,000. 



Abstract of Report. — During the past year nearly all the necessary 

 sections for the anatomy of the eye of Stygicola were cut and corre- 

 spondence was carried on concerning the rearing of the blind fishes 

 at the Tortugas Station. During June and July Mr. John Hose- 

 man, accompanied by Mr. Mclndoo as volunteer assistant, was col- 

 lecting in the caves of Cuba to secure embryos. It is expected that 

 the final report of the work will be presented shortly". 



