1851.] 349 



4. Manacus flaveoltis, nobis. 



Form. Very similar to those of M. gutturosus, (Desm.) and M. Candei, 

 (Parz.) 



Dimensions. Total length of skin from tip of bill to end of tail about SJ inches, 

 wing 2, tail about 1| inches. 



Colors. Very similar to those of M. gutturosus, but with the parts which are 

 white in that species, pale yellow in this. Top of the head, back, wings and 

 tail, black ; throat, breast, shoulders and broad collar around the back of the neck, 

 pale yellow, running into cinereous on the abdomen. 



Hab. Bogota, New Grenada. 



Obs. Two specimens of this little bird are in the collection, labelled as com- 

 ing from Bogota, and both presenting the singular variation in color, from the 

 common M. gutturosus^ on the strength of which I have considered it specifically 

 distinct. In point of color it may be stated as intermediate between M. guttur- 

 0S71S and Candei. It is smaller than the latter. 



5. Picics thyroideus, nobis. 



Form. Similar to that of P. varius, Linn., but rather larger and stouter, wings 

 with the third quill longest, legs and toes rather slender, tail rather broad. 



Dimensions. Total length of skin from tip of bill to end of tail about 8| inches, 

 wing 5|, tail 31 inches. 



Colors. 9 Breast with a large transverse patch or belt of black; middle of 

 the abdomen pale yellow. Head and throat brownish buff, with obscure longi- 

 tudinal stripes of black, back, wing coverts, sides of the body beneath and under 

 tail coverts striped transversely with black and sordid yellowish white, rump 

 and upper tail coverts white, the latter with black marks on their outer webs ; 

 quills, and tail black, more or less spotted with white. 



Hab. California, discovered by Mr, John G. Bell, of New York. 



Obs. Mr. Bell's two specimens are females, and are as yet unique. This 

 species is a strict congener of Picus varius, Linn., but does not resemble it in 

 colors, nor any other species which I have met with. 



The Committee on Dr. Leidy's paper entitled, " Contributions to Hel- 

 minthology/' reported in favor of publication in the Proceedings. 



Contributions to Helminthology. 

 By Joseph Leidy, M. D. 



MICR0ST0MUM1 Oersted. (Eustomum.) 



Body elongated, compressed cylindroid, vibrillated ; increasing by transverse 

 segmentation in pairs. Head continuous with the body, furnished upon each 

 side with a respiratory fovea. Mouth antero-inferior ; intestinal canal produced 

 anterior to the mouth in the form of a coecum ; cesophagus amphoraform, mus- 

 cular, not protractile ; anus at first (after segmentation) open, afterwards 

 becoming closed. Ocelli none. Minute rhabdoccela inhabiting fresh, water. 



This genus is the Microstomum of Oersted, if what I have observed to be 



