98 MR. H. CHARLTON BASTIAN'S MONOGRAPH 



External Characters. — Body tapering slightly anteriorly, but gradually to a point 

 posteriorly. Head truncate ; no setse. 



(Esophagus ^th of total length. Intestine rather thinly covered with fat-particles. 

 Anus 2^" from j)osterior extremity. Spicules slightly enlarged at upper extremities, 

 Tk" long. 



Female, not seen. 



Eab. Sandy mud from stream, Falmouth. 



4. M. LONGICAUDATA, n. sp. (Plate IX. figs. 5, 6.) 

 Female, length -^", breadth -^^o"- 



External Characters. — Body tapering slightly anteriorly, more considerably behind 

 vulva, and terminating in a very long filiform extremity. Head truncate; no setae. 



Oesophagus about ^th of total length. Intestine rather thinly covered with fat-par- 

 ticles, having indistinct tessellation. Anus -j^-" from posterior extremity. Vuloa near 

 middle of body. Uterus unsymmetrical. 



Male, not seen. 



Hah. Fine sedimentary sand, pond, Tunbridge Wells. 



5. M. FiLiFOBMis, n. sp. (Plate IX. figs. 7, 8.) 

 Female, length -^' , breadth ixrr"- 



External Characters. — Body long and narrow, scarcely tapering at all anteriorly, but 

 narrowing behind valva, and thence onwards, so as to terminate in a long filiform extre- 

 mity. Head truncate ; no setae. 



ffiso^jZ/rt^?;* yth of total length. Intestine sparingly covered with fat-particles. Anus 

 ■j-g-o" from posterior extremity. Vulva considerably behind middle of body. 



Male, not seen. 



Hah. About liverwort, from pier of bridge just above water-level, river Blackwater. 



6. M. DISJUNCTA, n. sp. (Plate IX. figs. 12, 13.) 

 Male, length -^' , breadth xst'- 



External Characters. — Body tapering slightly anteriorly, and also gradually to a point 

 posteriorly. Terminal sucker small; another large and prominent in the mid- ventral 

 region, two" from posterior extremity. Head rounded ; no setae. Integument plain, 

 having a circular depression on each side of head xowo" ^ diameter. 



Fharyngeal cavity yqyj small, conical. ■ (Esophagus about ^th of total length. Intestine 

 having a sphincter with traces of a valvular apparatus occupying its commencement, 

 which is devoid of granules ; remaining portion covered by very large cells, apparently 

 arranged in two rows. Anus 3X2" from posterior extremity. Genital duct oj)ening 

 separately 20^00" above anus. Spicules at anal cleft, slightly curved, -^^" in length, with 

 two (?) small triangular accessory pieces. Spermatozoa linear, tttoo" long, having slowly 

 undulating movement. 



Female, not seen. 



Hah. Marine, in sand from tide-pool, Falmouth. 



