84 MB. E. J. MIEES ON THE IDOTEID^. 



the A¥yandotte and Mammoth Cayes, which also inhabit wells in 

 Orleans, Indiana, do not, as Dr. Packard at first supposed, 

 belong to the Idoteidce, but to the Asellidoe ; and the so-called 

 egg-sacs are uropoda (see Packard, 5th Annual Eep. of Peabody 

 Acad, of Sciences, 1873, p. 94, and S. I. Smith, Eep. U.S. Fish 

 Commission, pt. ii. p. 661, 1874). Specimens apparently belong- 

 ing to OoBcidoteastygia are in the British Museum from the Ken- 

 tucky Caves (Gr. Lewis, Esq.) ; but they are dried and in imper- 

 fect condition, and appear to have lost the uropoda. 



The genus Slabherina of v. Beneden (Mem. Acad. Bruxelles, 

 xxxiii. p. 88, 18G1) was placed by this author in the Idoteidce, 

 but is without the characteristic operculum of the family ; it is 

 apparently synonymous with Etorydice, Leach. 



The following species are too insufl&ciently characterized for 

 me to assign to them their exact position in the system ; pro- 

 bably some of them may even not belong to this family : — Idotea 

 {Cymothoa) americana, Pabr. ; Idotea clielijpes (Pabr.), Latr. ; 

 Idotea fasciata, Latr. 



Hope, Cat. Crust. Ital. p. 26 (1851), refers to two species of 

 which I have seen no descriptions — Stenosoma denticulatum, Eisso, 

 from JSTice, and Leptosoma ohtusicauda, Costa, from Naples. 



EXPLANATION OF THE PLATES. 



Plate I. 



Fig. 1. Dorsal view of head and antennal region of Glyptonotus entomon 

 (Linn.), showing the position of the dorsally situated eyes, and the 

 form of tlie lateral cervical lobes, of the anteunules, antennae, &c. 

 X Ig- diam. 



2. Operciilar valve, or modified uropod, of the same, viewed from the 



inner side, showing the position of the minute outer ramus, which is 

 overlapped and concealed by the larger inner ramus. Nat. size. 



3. Dorsal view of head of Glyptonotus Sabini (Kroyer), showing the 



structure of the antero-lateral cervical lobes, eyes, antennules, and 

 antennae, as in fig, 1. X 1|- diam. 



4. Opercular valve (modified uropod) of the same, showing the form of 



the inner and outer rami, as in fig. 2. Nat. size. 



5. Glyptonotus Sabini (Kr.), young individual from Picton-Eoct Glacier, 



X 2 diam. 



6. Idotea Whymperi, n. sp., dorsal view, considerably magnified. 



7. Outer view of one of the opercular valves of the same, considerably 



magnified. 



8. Idotea ochotensis, Brandt, dorsal view of an adult specimen from Yedo 



Island, Japan, X I2 diam. 



9. Maxillipede of the same, considerably magnified. 



