EAST KENT NATURAL HISTORY SOCIETY. 13 



for the purpose. Thus costly accessories, such as achromatic 

 condensors, Webster's condeusor, Eeade's prism and hemispherical 

 condeusor, and other contrivances for providing suitable illumina- 

 tion are used, much to the profit of opticians. But, Col. Horsley's 

 experiments raise the question whether these expensive appli- 

 ances may not be altogether discarded ; and though this cannot yet 

 be affirmed, he exhibited in a very simple manner the markings of 

 the valves of Pleurosigma. This was done by taking the light in 

 a plane with the object, and dispensing with the glass reflector 

 and the condenser, so that the only reflected light was derived 

 from the inside of the short plated tube under the stage of the 

 microscope ; and the luminous rays thus faintly and obliquely 

 transmitted proved quite efficient in rendering the markings 

 plainly visible under objectives of one fourth of an inch focus. 



2. On Points in the Intimate Structure of British Euphorhiaeece ; 

 by Mr. Grulliver. — Referring to his memoir on the Latex 

 of plants, published in the 'Annals of Natural History' for 

 March, 18G2, the author announced that he had some new 

 points to display to the meeting. Selecting first a fresh specimen 

 of Mercurialis annua, he showed that this plant abounds in 

 Sphferaphides, and to such an extent that it afibrds an excellent 

 indigenous exemplar of them. And the interest of this fact is 

 increased, because it presents a good diagnostic between the genus 

 Mercurialis and all the other British Euphorbiacese ; and this 

 character, though so easily seen, is quite ignored in the systematic 

 and other works on botany. Nor is it less noteworthy that the 

 very curious starch-sticks of Muphorhia afford an equally distinct 

 and sharp character of this genus among the British Euphorbiacese ; 

 these rods of starch not having yet been found in any British 

 plant of other orders, if, indeed, in any other order native or 

 exotic. Tlie author observed that such characters in this point 

 of view, including those afi"orded by raphides, hairs and cells of 

 the epidermis of Phanerogams were of great importance, and that 

 it seemed remarkable that only Dr. Lankester and Professor 

 Balfour had yet at all recognised this valuable addition to 

 taxonomic botany. 



September 2'Sth. — Scenuris variegata. — Specimens of this worm, 

 each about an inch in length, and collected at Canterbury, were 

 exhibited at the meeting. Whereupon the Honorary Secretary and 

 Vice-President (Mr. Gulliver) gave descriptions as follows : — The 

 present animal is a meinber of the Bristle-footed Worms {Anne- 

 lida setigera, s. Chcetopoda). These being devoid of gills or other 

 special organs for breathing, and commonly androgynous, are 

 known to zoologists as Abranchiate and monoecious Annelida. 

 As shown at a former meeting, the respiratory function 

 in this family is probably carried on by means of the vibratile 

 cilia with which these creatures are so plentifully supplied 

 within the intestinal canal and elsewhere. They have a 

 distinct ventral nervous chain with ganglia ; and a well-marked 

 vascular system, of which the great vessel on the back is the 



