NATURAL SCIENCES OP PHILADELPHIA. 365 



cially sheep, in whicli it caused the disease called "rot." The 

 worm exhibits some ditlerences from D. hepaticum as usuall}' de- 

 scribed, but perhaps not sufficient to characterize it as a distinct 

 species. The specimen is preserved in strong alcohol, which no doubt 

 has much contracted and reduced it in size, but it is yet rather 

 larger than the size assigned to D. hepaticum. It is perfectly 

 smooth throughout, and exhibits no trace of roughness to the in- 

 tegument. It is ovate-lanceolate in form, and gradually widens 

 from the anterior to the posterior rounded extremity. The ventral 

 acetabulum is twice the size of the mouth, and is situated about 

 its own diameter behind it. The genital orifice with the exserted 

 spiral penis is placed just in advance of the ventral acetabulum. 

 The measurements of the worm in its present condition are as 

 follows: Length H lines, width at the posterior third 7 lines, 

 thickness near centre 1 line, diameter of mouth fths of a line, 

 diameter of acetabulum |ths of a line. 



Prof. Leidy further remarked that Dr. Keyser, of this city, the 

 evening previously had brought to him for examination a worm, 

 which was stated to have been removed from the cavity of the nose 

 of a patient. He recognized the worm as a rat-tail lava, appa- 

 rently of the genus Erisfalis, and inquired of those members in- 

 terested in entomology^ if they had ever known this insect to be 

 found as a parasite in the human body. Both Drs. LeConte and 

 Horn said that they had never heard of this genus being parasitic. 



Analysis of Chromite from Monterey County., California. By 

 E. Goldsmith No analysis of chromite from this locality, so far 

 as I am aware, has yet been published. Mine was undertaken 

 with the view to ascertain what particular relation it might have 

 to Trautwinite. As the last-named mineral is found on it, I pre- 

 sumed that the latter might have originated from the former. A 

 chemical analysis only could decide the question. The process 

 pursued was in all respects the same as that followed in mj' pre- 

 vious investigation of Trautwinite; not omitting great care in 

 the preliminary mechanical separation of the two species from 

 each other. The following table gives the result of both analyses 

 and a comparison of the two minerals, together with the ditfer- 

 ences : 



S. 



The formation of Trautwinite from chromite may be conceived 

 to have taken place in accordance with the neptunian hypothesis, 

 by the combination of silica and lime with the chromite, thus pro- 



