Dr. E. A. Andrews on a new Species of Plioronis. 445 



Tunis, north of the Sahara, and the intermediate islands; also 

 Tripoli, -Egypt, North-west Arabia, and Abyssinia. 



D. Var. vittatus. 



30-34 scales round the body (usually 32). Bronzy brown 

 above, without ocelli ; a light upper and a black lower lateral 

 band. From snout to vent 115 millim. 



Only known from Tangiers, where no other form occurs. 



E. Var. polylepis. 



34-40 scales round the body (usually 36-38). Dark brown 

 above, usually with a small round yellowish spot on each 

 scale ; sides of neck with vertical black and white bars, which 

 disappear in the adult. From snout to vent 150 millim. 



Morocco. First noticed by Boettger from Casablanca, 

 Mogador, and the city of Morocco. Nine specimens from the 

 city of Morocco and four from Casablanca are now in the 

 Natural-History Museum. 



LVII. — On a neto American Species of the remarkable animal 

 Plioronis. By E. A. Andrews, Ph.D., Johns Hopkins 

 University, Baltimore, U. S. A. 



Plioronis architecta, sp. n. 



The following manifestly imperfect, notice of an American 

 form of the interesting genus Plioronis is published with the 

 desire of calling the attention of embryologists to its existence 

 in the hope that it may thus be the sooner known and perhaps 

 included in a needed monograph of the group rather than 

 from any desire of adding a new species to the present list of 

 five or six, some of which are also insufficiently described. 



The animal was found at Beaufort, N. C, in June 1885, 

 inhabiting slender tubes standing upright in rather impure 

 or muddy sand, both immediately in front of the building- 

 then occupied by the Chesapeake Laboratory and also upon 

 " Shark Shoal/' 



The tubes are isolated and separate, each a clear, firm, 

 chitin-like membrane passing down many inches into the 

 sand and slightly projecting above its surface in regions laid 

 bare at low water. The upper part of this tube is covered 

 with a layer of sand, which seems as if selected, being com- 

 posed of rounded grains of clear silex with a few of milky 

 quartz, and no dark grains at all. 



