26 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
cloacal opening large, circular, Head laterally compressed, somewhat 
pointed ; cuticle with irregular prominences, which are figured. Or, in 
the words of his own diagnosis: “Corpus nigrum verrucosum, medio 
cylindricum, utrinque attenuatum depressumque, linea ventrali et dorsali, 
quarum parti caudali fasciculi pilorum insiti. Caput ellipsoideum, con- 
cavitate frontali. Extremitas caudalis trigona, apice rotundata.” This 
is a good species. 
1856. Leidy gives a much fuller description of his @. varius. He 
also describes G. robustus, n. sp., and places synonymous with it G. seta 
Müll., and G. lineatus Leidy. 
1857. The same author mentions a collection of 48 Gordii, 525 miles 
west of Fort Riley, Kansas. 
1858. Leidy notes the occurrence of an embryo of G. varius in Lum- 
briculus limosus. 
1861. Diesing regards G. platyurus and fasciatus Baird as good 
species; as also G. varius Leidy, with which he considers synonymous 
the “ G. aquaticus” of Leidy, '51. He considers Leidy’s lineatus and 
robustus as doubtful synonymes of G. seta Müll. (aquaticus Linn.). Die- 
sing also describes G. subspiralis, n. sp.: “Corpus maris brunneum, 
feminæ antrorsum attenuatum, late brunneum, nitidum, iridescens. 
Caput annulo obscure brunneo cinctum. Extremitas caudalis maris 
subspiralis crucibus furc® terminalis divergentibus, incurvatis, levibus, 
plica membranacea semilunari ad basin junctis, feminæ obtusa, subcom- 
pressa. . ... In palude cum Siredonibus, copiose, in territorio Kansas 
(Hammond).” 
1866. Schneider regards G. varius Leidy as a possible synonyme of 
G. gratianopolensis Charvet (G. tricuspidatus Meissn.). 
1874. Villot regards the following as good species: G. lineatus, 
robustus, and varius of Leidy; G. subspiralis and G. chordodes of Diesing ; 
and G. chilensis Blanchard. He describes the following new species from 
America: — G. æneus, n. sp.: “Extrémité antérieure tronquée, légère- 
ment renflée. Ouverture ano-génitale du mâle entourée d’un anneau 
brun. Lobes bien développés, séparés par un assez large intervalle. 
Brun bronzé. (Les jeunes individus sont d'un blanc jaunâtre uniforme.) 
Epiderme divisé en losanges par un réseau de lignes saillantes oblique- 
ment croisées”; from Cumana, Venezuela. G. reticulatus, n. 8p.: “ Ex- 
trómitó antérieure terminée en pointe aiguë. Diamêtre du corps allant 
en grossissant de l’extrémité antérieure à l'extrémité postérieure, qui 
se termine en point tronqúee. Ouverture ano-génitale large. Brun 
marron. Une bande dorsale et une bande ventrale d’un brun plus 
