38 ANNUAL REPORT OF THE 



REPORT ON THE ECHINODERMS, POLYPS, ETC. 



By Alfred G. Mayer. 



The time of the Assistant has been mainly devoted to a general 

 inspection and revision of the collection. 



Many of the ink written labels of the alcoholic specimens had 

 faded to such an extent as to be almost illegible. This was espe- 

 cially true of the Pourtales types of Deep-Sea Corals. Several 

 hundred labels were copied and replaced. In only two cases was 

 it found impossible to decipher the original label. 



The Assistant has added to the collection about thirty species of 

 Medusae, preserved in 5% formalin. 



These were for the most part obtained at the Newport Laboratory. 

 In addition to the above, about twenty-five species of Hydromedusaa 

 from the Dry Tortugas, most of which are new to science, have 

 been placed in the collection. 



It is found that excellent Museum specimens of Medusas may 

 be made by killing and preserving them in 5% formalin. In many 

 cases the animal is preserved in a perfectly natural attitude, and 

 the gelatinous substance of the bell, etc. remains transparent. 

 The colors of the proboscis, etc., however, usually fade, and the 

 specimens are not suitable for histological work. 



The Assistant has published " A New Hypothesis of Seasonal- 

 Dimorphism in Lepidoptera," in Psyche, a Journal of Entomology, 

 May -June, 1897. 



