ISOPODS OF NORTH AMERICA. 625 



The first two abdominal segments have the lateral parts undeveloped. 

 The third, fourth, and fifth segments are broadly expanded laterally, 

 the outer margins forming a continuous and unbroken line with the 

 margins of the thoracic segments. The terminal segment of the abdo- 

 men extends but a distance of half its length beyond the lateral parts 

 of the preceding segment; its surface is smooth. The basal joint of the 

 uropoda attains half the length of the terminal segment. The inner 

 branch reaches the apex of the last segment. The outer branch extends 

 half its length beyond this. 



Two specimens were collected by Prof. A. E. Verrill and party at the 

 Bermudas in 1898. They were found in dead coral at Castle Harbor. 



Type in Peabody Museum, Yale University. Cat. No. 3333. 



This species can not be identified with any of the described species 

 of the genus: L. panzerii (Audouin and Savigny), L, tauricus Budde- 

 Lund, L. squamatm Budde-Lund, and L. a lentus (Budde-Lund), 

 although it seems more closely related to the last named than to any 

 of the former. 



111. Genus METOPONORTHUS Budde-Lund.& 



Body oblong, depressed, not convex, scarcely contractile. 



Head marginate and with lateral lobes very small; frontal lobe want- 

 ing; vertical marginal line extending to the lateral lobes; second pair 

 of antennae long; flagellum composed of two articles, the first article 

 generally longer than the second; abdomen abruptly narrower than 

 the thorax, with the lateral parts of the third, fourth, and fifth seg- 

 ments small, appressed; terminal segment short, triangular, extending 

 moderately beyond the lateral parts of the preceding segment; oper- 

 cular plates of the first two pairs of pleopods furnished with tracheae, 

 rarely those of the third or of all the pairs furnished with tracheae. 

 Inner branch of the uropoda inserted far in front of outer branch, 

 near the inner antero-lateral angle of the peduncle. 



ANALYTICAL KEY TO THE SPECIES OF THE GENUS METOPONORTHUS. c 



a. Lateral parts of the third, fourth, and fifth segments of the abdomen well 



developed Metoponorthus saussurei Dollfus. 



a'. Lateral parts of the third, fourth, and fifth segments of the thorax reduced, small. 

 b. Epistome furnished with a sinuated transverse line. 



o. Second pair of antenme equal to three-fifths the length of the body. First 

 article of the flagellum much longer than the second. Inner face of right 

 mandible furnished with four to five penicils, of the left with six penicils. 

 Terminal segment of abdomen almost flat. Color brown or reddish brown, 

 often mottled with white spots Metoponorthus pruinosus (Brandt) . 



See Dollfus, Mem. Soc. Zool. de France, 1896, pp. 542-543. 



& For characters of genus see Budde-Lund, Crustacea Isopoda Terrestria, 1885, pp. 

 161-162, and Sars, Crust, of Norway, II, 1899, pp. 183-184. 



c This key has been prepared entirely from the descriptions of the forms, which 

 give few characters for a synoptical arrangement. 

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