STATE GEOLOGIST. 169 



If this form be worthy a distinctive name, it may be called 



Sp. 2. Canthocamptus tenuicaudis. (Sp. n.) 

 (Plate 0. Figs. 15 and 16.) 



? Sp. 3 . Canthocamptus brevipes, Sars. 



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

 species; yet I transcribe the description. 



"Corporis forma et magnitudine G. pygmseo non dissimilis. Segmenta abdominalia 

 vero postice magis attenuata seriebusque aculeorum destituta. Rami caudales elongati 

 •duplo longiores quam latiores, setis apicalibus brevisculis parumquedivergentibus, ex- 

 teriore dimidiam longitudinem interioris non attingente. Operculum anale absque 

 dentibus. Antennae 1-mi paris breves, articulis ultimis duobus in unum confluentibus 

 articulum. Pedes natatorii brevissimi, ramo exteriore intus setis destituto, interiore 

 biarticulato in pedibus 1-mi paris longitudinemjexteriorissequante, in sequentibusmulto 

 breviore. Pedum 5-ti paris articulus basalis intus in processum follifoiunem, sat mag- 

 num et angustatum, articulum ultimum elongato-ovatum aliquanto superautem, exit. 

 •Color albidus . Longit . parum supra i/4 mm . " 



Sp. 4. Canthocamptus crassus, Sars. 



«) 



Robust; segments margined with pectinate bristles. Caudal 

 stylets oval, contorted, constricted at the base. Antennas thick, 

 densely covered with long setae. Fifth feet with long setse; basal 

 process rather small. All the feet excepting the first, with bi- 

 articulate inner rami. Length 0,75 mm. 



Sp. 5. Canthocamptus trispinosus, Brady. 



(Plate 0, Figs. 6—14.) 



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

 with bi-articulate 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 un- 

 linown. Not yet identified in America. 



Sp. 6. Canthocamptus northumbricus, Brady. 



Body robust; antennae long as first segment, nine-jointed; man- 

 dibular palp minute. In the male the inner branch of the third foot 

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



