130 GEOL. AND NAT. HIST. SUHVEY OF MINNESOTA. 



Caiithocaniptiis brevipes Sars. 



This small form is almost certainly the young stage of some other 

 species; yet I transcribe the description: 



" Corporis forma et magnitudine C. pygmajo non dissimilis. Segmenta abdomi- 

 nalia vero postice magis attenuata seriebusque aculeorum destituta. Rami caudales 

 elongati duplo longiores quam latiores, setis apicalibus brevisculis parumque diver- 

 gentibus, exteriore dimidiam longitudinem interiorisnonattingente. Operculum auale 

 absque dentibus. Antennse 1-mi paris breves, articulis ultimis duobus in unum con- 

 fluentibus articulum. Pedes natatorii brevissimi, ramo exteriore intus setis destitute, 

 iDteriore biarticulato in pedibus 1-mi paris longitudinem exterioris aquante, in 

 sf quentibus multo breviore. Pedum 5-ti paris articulus basalis intus in processum 

 foliiformem, sat magnum et angustatum, articulum ultimum eJongato-ovatum aliqu- 

 anto superantem, exit. Color albidus. Longit. parum supra j mm." 



Canthocamptus crassus Sars. 



Eobnst; segments margined with pectinate bristles. Caudal stylets 

 oval, contorted, constricted at the base. Antennte thick, densely 

 covered with long setse. Fifth feet with long setse; basal process 

 rather small. All the feet excepting the first, with biarticulate inner 

 rami. Length 0.75 mm. 



Caiithocaiiiptiis trispinosus Brady. 

 Plate L, Fig. 6. 



This species with the last and next has all the feet save the first 

 with biarticulate inner rami. Very near the next, from which it 

 differs in the form of the fifth foot of the female, which has the basal 

 process smaller, bearing only three spines, while the next has six, the 

 second joint being longer and narrow. The male is unknown. Not 

 yet identified in America. 



Cantliocamptus northuiiibriciis Brady. 

 Plate XXIX, Figs. 20-22. 



Body robust; antennse long as first segment, nine-jointed; mandi- 

 bular palp minute. In the male the inner branch of the third foot is 

 three-jointed and dactylate. as in C. minutus. 



* Cantliocamptus uorthuiubricus Brady. Var. ainericauiis Herrick. 

 Plates XXIX, Figs. 6-14; XXXIII, Figs. 3-5. 



One of our most common species is very near the English form; so 

 near, in fact, that I dislike to remove it from it. A few points of 

 divergence, however, may be mentioned. 



The form and proportions are much like those of (7. minutus. The 

 head is large and ends in a prominent bent beak. The anteunce are 



