THE AMERICAN 



MONTHLY 



MICROSCOPICAL JOURNAL. 



Vol. IX. NOVEMBER, 1888, No. 11. 



Rinnbock's Slide of Arranged Diatoms, Chirodota Wheels, Synapta 

 Plates, Synapta Anchors, etc. 



By CHAS. W. smiley 



The arrangement of 2S9 microscopic objects inside the space of a pin-head 

 is a noteworthy accomplishment. When, in addition, tlrey are made to 

 present a regular and harmonious picture of great beauty, some praise ought 

 to be accorded the artist. In the case illustrated by the frontispiece, the work 

 was performed by Mr. J. C. Rinnbock of Wien, Austria. The slide is now 

 the property of Miss M. A. Booth, of Longmeadow, Mass., who has kindly 

 consented to have the engraving made and who has identified the objects. The 

 slide was recently photographed by Mr. W.O. Tasker, of Haverhill, Mass., 

 and his photo-micrographs are beautiful specimens of the art. From one 

 of these a photo-engraving company has made an engraving by the ' Half- 

 tone process,' thus enabling the printer to make copies by the ordinary print- 

 ing press. Considerable skill was, however, necessary in putting it upon 

 the press, keeping it clean and working it carefully. Mr. John Gibson, of 

 the firm that prints this periodical, kindly gave his personal attention to the 

 work. The engraving, of course, falls short of the photograph, and even the 

 photograph does not reveal the colors and other beauties of the objects. It 

 is to be hoped that Miss Booth will exhibit the slide at the next meeting of 

 the American Society of Microscopists. 



In order that all, whether microscopists or not, may understand the engrav- 

 ing, a brief description of its contents is appended. 



The central object is a diatom of the family Coscinodiscecc. genus Coscin- 

 odiscus. The beauty of this object, due to the regularity of hexagonal 

 areolation of the valves, does not appear in the engraving. A description 

 and good figure will be found in Dr. Carpenter's work, The Microscope, 



PP- 347-8- 



First and Second Rows. — The two rows next to the central object contain 



32 wheel-like plates from the skin of Chirodota., a Mediterranean genus of 



Holothurian. Under the microscope they present a singular beauty and 



delicacy of notching around the inner margin of the tire of the wheel. 



(cf. Carpenter, p. 641). 



Third Row. — The third row from the centre is made up of 16 specimens 

 of the genus Actinocychts, — a diatom closely related to Coscinodiscus, The 

 difference is in the marking of the disks but cannot be clearly seen in the 

 plate. In this case there are dotted lines radiating from the centre. Un- 

 fortunately the photo-engraving does not show the beautiful shades of brown, 

 red, blue or purple which the object reveals under the microscope. 



Fotirth Row. — This consists of i6 Chirodota wheels, like those in the first 

 and second rows. 



Copyright, 1888, by Chas. W. Smiley. All rights reserved. 



