286 [October, 



Habitation. In the mud about the roots of Pontederia cordata, Sagitaria sagi- 

 tifolia, and Arum virginicum, in ditches below Philadelphia. It is also often 

 found coiled up in a remarkably close knot, among the outer decaying petioles 

 of the leaves of the plants just mentioned. Months of August and September. 



2. LlIMBRICULUS HYALINTJS, Leidy . 



Acestus hyalinus, Leidy: Proc. A. N. S. v, 226. Description from the young 

 in the Spring. 



Adult. Body filiform, red in color, the posterior fifth yellowish, translucent. 

 Upper lip sub-acute. Caudal annulus obtuse. Annuli from 120 to 180. Podal 

 spines in fasciculi of from 3 to 8, furcate. 



Whole length 2 inches, with usually 150 annuli; breadth anteriorly l-5th line, 

 posteriorly l-6th line. One of 1 inch is about l-6th line anteriorly, l-8th of a 

 line posteriorly. 



Habitation. Found in ditches with the preceding, the anterior two-thirds of 

 the body hurried in the mud, with the tail rapidly vibrating like Saenuris or 

 Strephuris. Months of August and September. 



CHiETODEMUS, Genus novum. 

 Body cylindroid. Upper lip very large and broad. Podal spines in 4 rows, 

 fasciculate, aristate. Mouth large, inferior ; pharynx capacious, oesophagus 

 cylindrical ; intestine capacious. Eyes none. Blood colorless. Increasing by 

 segmentation. 



1. Ch/etodemus pandueatus, Leidy. 



Body transparent, colorless. Upper lip panduriform, broader than the body. 

 Podal spines in fasciculi of 4, long sigmoid, aristate, divergent, l-666th in. long, 

 commencing with the oral segment. Pharynx oval ; oesophagus narrow, cylin- 

 drical ; intestine large, narrowing posteriorly. 



Whole length of an individual of three segments 1 line ; breadth l-570th inch. 

 Breadth of upper lip l-500th inch. First segment of the body with 7 annuli ; 

 second with 5 ; the third with 9. 



Habitation. Found in stagnant ponds and ditches. 



Remar/c, Allied closely to iEolosoma. 



STYLARIA, Lamarck. 



1. Stylaria paludosa, Lamarck. 



Nais proboscidea, Linn. Syst. Nat. 13th ed. vol. i, pt. 6, p. 3121. 



Body cylindroid, colorless, transparent. Without segmentation from 15 to 20 

 annuli ; one of two segments 40 annulations. Podal spines, 7 to 10 in each 

 fasciculus, long sigmoid, hooked and bifid at the free end. Setae commencing 

 after the fifth annulus from the mouth, usually single, occasionally two, from 

 l-400th in. to l-66th in. in length. Caudal annulus truncated, sinuous, fringed 

 with short stiff hairs. Upper lip broad, emarginate, with a cylindroid, flexible, 

 proboscidiform appendage from the l-33d to the l-25th in. long projecting from 

 its notch, fringed with short, stiff hairs. Eyes two, transverse reniform, situated 

 one on each side of the mouth. Mouth triangular ; pharynx capacious, oesophagus 

 cylindrical, terminating in the intestine at the third setous annulus. 



