348 ZOOLOGY. 



the foot of Tethys,* but at tlie same time it is coDJectured that it does not 

 reside there permanently. This form has not been named, but has been 

 considered to be closely allied to GraffiUa muricicola. The pharynx was 

 feebly developed and appeared to be destitute of a sheath. No peripheral 

 nerves or special organs of sense or water- vessels were observed. The 

 female organs were well developed; but in none of the specimens 

 examined could the male organs be detected except in a rudimentary 

 condition. 



THE GROUPS OF NEMERTEAN WORMS. 



The Xetnertean worms have been examined with relation to their genera 

 and systematic relations inter se by Dr. A. A. W. Hubrecht.t It is claimed 

 that the genera proposed for the European forms must be reduced to four- 

 teen. These are grouped, first, into two sections, one distinguished {Hoplo- 

 Tiemertini) hy the mouth being in front of the ganglia and the proboscis 

 furnished with stylets, and the second {nameless) by the mouth situated 

 behind the ganglia and the proboscis destitute of stylets. The latter are 

 subdivided into (1) Schizonemertini, distinguished by the development 

 of a deep lateral fissure on both sides of the head; and (2) Palceonem- 

 ertini, characterized by the absence of such fissures. The three groujis 

 so named are designated as ^^ suhordersP 



The suborders are essentially the same as the three families generally 

 admitted, and which are much better so designated than as suborders. 

 The genera admitted are segregated under nine families, and are, for (1) 

 the Hoplouemertini, Xemertes, Oerstedia, Frosorhochnius, Tetrastemma, 

 Amphiporiis, and Drepanophorus ; in (2) the Schizonemertini, Langia, 

 Cerebratulus, Borlasia, and Lineus, and in (3) the Pala?onemertini, 

 Valeneinia, roUa, Cephalothrix, and Carinella. (Condensed from J. B. 

 M. 8.) 



The author seeks to determine the phylogeny of these forms, but 

 the data apparently are not sufficient for such jiurpose. 



A PARASITIC NEMERTEAJSr. 



More than a century ago (in 1779) O. F. Miiller described a worm which 

 has, until lately, been regarded as being a kind of leech. This form 

 has been named Malacohdella grossa, and the specimens occur parasitic 

 in Cyprina Islandica. As indicated by the name, Malacohdella is charac- 

 terized by a very soft body, and its width is nearly the same as the 

 length, except in the region of the sucker ; its muscular system is charac- 

 teristic ; the mouth is placed at the anterior end and is a transverse 

 cleft ; the proboscis is white, and is destitute of any armature or spines ; 

 the pharynx very white and visible through the transparent integument ; 

 the intestine narrow and dark. On account of this union of characters 



* Lang (Arnold). Notiz iiber einen neuen Parasiten der Tethys aus der Abtheilung der 

 rhabdocoel en Turbellarien. Mittheil. Zool. Station Xmpel, vol. ii, pp. 107-112. 



+ Hubrecht (A. A.W. ). The Genera of European Nemerteans critically revised, with 

 deBcriptions of several new species. Notes Mua. Leyden, No. iv, pp. 193-233. 



