244 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxvi. 



to the Galapagos Islands in 1891; also 38 species and subspecies dredged 

 by the Indian survey ship Investigator since 1884 have been described 

 by Wood- Mason or by Alcock and Anderson. 



Family GALATHEID^E. 



The Galatheidii?, as has often been pointed out by recent writers, 

 belong to the Macrura Anonialia, but with more or less brachyuran 

 relationships. 



In form they resemble the true Macrura, and are closely related to 

 the Porcellanida% which at iirst sight, on account of their form and 

 habits, would be placed with the Brachyura. 



Most of the Galatheida? live on the bottom and, with the exception 

 of a few forms like Grimothea and Pleuroncodes, probably do not 

 swim freely to any great distance. Some of the genera are blind, 

 inhabiting deep water and even ab3^ssal depths, others again have a 

 well-developed cornea divided into facets. While man}' Galatheids 

 must prefer a sea bottom atiording numerous hiding places, others, 

 as some of the genus Uroptychus^ are well fitted for climbing on 

 sponges, hydroids, or corals. 



Occasionally a specimen will be found with a small worm tube on 

 its carapace, though usually they are as completely free from any 

 foreign growth as are any of the more active Crustacea. More fre- 

 quently the carapace will be distorted by the presence of an Isopod 

 parasite in the branchial chamber. 



This family presents problems in classification of considerable 

 interest. The genus 3fvnidopsis, as now constituted and upheld by 

 some good natui'alists, is made to include several of the genera estab- 

 lished by A. Milne-Edwards. In a long and able article* on the sub- 

 ject, A. Milne-Edwards and E. L. Bouvier contend for the generic 

 distinctness of the groups. With the groups united in one genus, 

 the species differ widely in form, more widely than is desirable, 

 because the name does not convey to the mind a sufiiciently distinct 

 picture of the forms designated by it. On the other side of the ques- 

 tion it may be said that if the genera were divided a satisfactory ke}'^ 

 could not be made on generic lines unless perhaps in the case of 

 Galathodes. 



The species placed in the genus Munida come fairly well under one 

 generic name, with the possible exception of one or more species some- 

 times placed under Grimothea, about which much has yet to be learned, 

 especially in regard to the young forms, which do not seem to have the 

 same development as the young of other species. Individual varia- 

 tions within the species are not uncommon. Sometimes the abdomen 

 will be unarmed, where usually it is armed. This is more often true 



« Considerations Generales sur La Famille des Galatheides, Ann. des Sci. Natr., (7), 

 XVI, p. 191, 1894. 



