INVERTEBRATA, ORTPTOOAMIA, MICROSCOPY, ETC. 807 



ones are the larger and more rigid. A digestive cavity appears to 

 extend throughout the body ; at one end, surrounded by hairs, is a 

 dilatable opening, which is lined by crystalline rods, as in Chilodon. 

 No other organs have been found. The only movements detected 

 were those of rotation round the long axis of the body, caused only by 

 the external cilia, and of a bending and displacement of segments, 

 probably due to contractile mesodermic tissue. 



Of the two kinds noticed, the larger are the females, which vary 

 from 'IS-* 15 mm. in length, with a breadth of '03 mm.; they 

 are dark green, and the surface appears to be finely punctate. There 

 are nine or ten quite distinct segments, followed by a terminal part 

 in which the segments are very indistinctly marked, but which per- 

 haps represents five more, thus agreeing in the main with the species 

 figured with some hesitation as Intoshia leptoplance by Keferstein. 

 The smaller individuals are less numerous, and measure • 1 by "02 mm. 

 They are hardly at all pigmented except at the posterior extremity ; 

 they are probably the males, but no male elements have been found 

 in them. The segaaents ajjpear to be about twelve or thirteen. Some 

 individuals show a strong median constriction, and some are found 

 in a kind of cyst. If the pi-esence of a digestive canal with two 

 openings should be established, the species will have to be excluded 

 from the Orthonedida. The name given to it (subject to its not being 

 proved to be identical with I. leptoplance) is P. Hessei. 



New Synthetic Type.* — At a meeting of the Zoological Section 

 of the Eussian Association of Naturalists, A. Kowalevsky gave an 

 account of Coeloplana Metschnikoivii, a new form which lives on 

 Zostera in the Eed Sea, and which constitutes a type intermediate 

 between the Coelentcrates and the Planarian worms. 



In its outer form it resembles a Planarian ; it is grey above, white 

 below, and about three lines in length by two in breadth. Like all 

 Planariaus, it crawls on the whole ventral surface, in the middle of 

 which is a slit-like oi)ening communicating with a four-lobed stomach 

 which resembles most nearly the " funnel " of the Ctenophora ; from 

 it originate a large number of canals which radiate to the perij)hery 

 of the auimal and open into a ring canal which bears many csecal 

 appendages. On the dorsal surface, almost directly over the mouth, 

 is a vesicle containing a number of vibratilc otolitlis. On either side 

 of this otocyst is a sheatli from which can be protruded a long retrac- 

 tile tentacle. Each tentacle is branched and corresjionds in shape to 

 those of Cydippe and Eschscholtzia, only they have no central canal, 

 but are composed of muscles. The nervous system and genitalia were 

 not observed. The whole surface of the body is covered with vibratile 

 cilia. 



Echinodermata. 



Development of the Echinodermata.f — Dr. Goethe states that, 

 when lately looking through some preparations of Bipinnaria made 

 by Herr Meyer at Naples, he observed a mode of development of the 



* 'Zool. Anztip.,' iii. (18S0) p. 140 ; see 'Am. Natural.,' xiv. (1880) p. 531. 

 t Ibid., Hi. (1880) p. 324. 



