HO THE AMERICAN MONTHLY [Apiil 



of that work to enlist in its ranlvs. No other stipulation 

 is made. It is a band olWorUers interested in each other's 

 pursuits and willint;- to ii"i\e and take \\hate\er aid their 

 union can supplw The\- do not set tlieinselves on a ]»in- 

 naele as experts and specialists but claim to l)e merely a 

 small comj)any \\orkin«i- 1<>1' the s^eneral j^-ood and well 

 aware that the humblest ol)server may V)e able to add 

 knowledg-e and experience that will be ol" \aluetoall. The 

 vearly subsciM])tion to the A. M. S. is two dollars with an 

 entrance fee of thi-ee dollars. In i-eturn for that the mem- 

 bers receive free a co|)y of the ])ul)lished papers of the 

 Society. 



Quekett Microscopical Club. Mr. W. Stokes g-ave a 

 description of some easih-made monochi-omaticlig'ht filters 

 for microscopical purposes. The subject was further dis- 

 cussed by Mr. Nelson, Mr. Rheinberg-, and others. Mr. 

 T. Rosseter read a paper ''Experimental Infection of the 

 Domestic Duck with Cysticerci or Larval Tapeworms." 

 Specimens and drawings were shown, by theauthor.of Dic- 

 ranotaMiia coroiuila and Cvsticercus coronuhu Dre])aniilot- 

 ecnia gracilis and Cysticercus g-racilis, D. tenuirostris and 

 Cvsticercus tenuirostris. in which cases he had proved by 

 direct experiment that the given Cysticerci were really 

 the larval forms of the tapeworms s])ecilie<l. and the mat- 

 ter was now no longer one of mere surmise from the iden- 

 tity of the booklets, &c. The secretary said Mi\ Kosseter 

 appeared to be the st)le investigator of the life hist«»ry of 

 this interesting grouj) of bird jiarasites in this country. 



Mr. Nelson exhibited anew triplet magnilier he had 

 computed with a working distance of s l<t in., a new ach- 

 romatic and aplanatic bull's-eye, and read a paper on the 

 secondarv structure id the diatom, Kittonia elaborata. 



In consecjuence of April l()th being (iood Friday, the 

 next ordinary meeting will be held on Friday. May 21si. 



The ColL'ge of Physicians and Surgeons, of Chicago, has 

 recently become the Me<lical School of the University of 

 Illinois. 



