129 



Oudemans^ does not mention these communications "Not only 

 from the 2 lateral vessels but from 



the Cephalic loop numerous bran- , t > . 



ches arise. In my specimens the /} ^_^,^ yi K^^^^^^^^^:^ t - '^^ ■ 



median had none." I , — '" — (/ i a—. .^r:C>.^J_....i) 



Bürger^ states: »Indessen }\jì (^ n ^f^ 



überzeugte ich mich nicht an M \ Ao / / /^Lj^) 



meinen Schnittbildern davon, ^ \ i/^ ^/ :^-ù^^cz\^.\-l^... ..ci. 



daß Rücken und Seitengefäße C\ I ["TT^ /)\r) \[\[ 



mittels ihrer Zweige mit einander \^ ^r\ [1 L/lJ^'-^y^/i j 



commissurieren fc. / |=:0 \\ c^ [7 



C. K. HoffmanG though I \\ 



ignorant of the presence of the / ^yç^J / /AI/^ T 



dorsal vessel correctly observes: J \ — ^J \ / ^i 



J) Medians-arts giebt jedes Seiten- ^ ^ r^''Vç\^ // //ir 



gefäß zahlreiche Queräste ab, die | )n lAv^^rc^ f/ "^ 



sich wieder theilen können und ri ^^ ^ \\ l^>^ ( 



so Anastomosen bilden, wodurch 6' ) \ JV/ // / r^ 



die Seitengefäße mit einander in w\ )\ ( / ö , 



Zusammenhang stehen«. 1 ) N ^-^ 



In M. japonica Takakura'^ 

 ,1 , • • 1 Fig. 5. Diagram of vascular prolongations 



these metamerie commissures and ^ ij..u- .. 



irom vessels and tneu- anastomoses, recon- 



their anastomoses have been de- strueted partly from serial sections, partly 



scribed, but the vascular trees of from observations on living animals (the 



,•1 -1 1 . ^ animal is supposed to be fully extended 



the pharyngeal region seem to ^ , r ,• r +u * * i i „+i, f 



r J ^ & and only a fraction of the total length ot 



have been absent. In nearly all the vessels is diagramatised). 



my specimens there were encysted 



trematodes embedded in the gelatinous tissue, while the intestine was 

 iisually occupied by gregarines in such numbers as to completely fill 

 the lumen. 



F= vascular tree, L — lateral vessel, D = dorsal vessel, C = Cephalic loop, 

 Ji = wall of Rectum immediately anterior to anus, 31. S. = margin of sucker, C. L. = 

 connection between lateral vessels, CD. = connection between dorsal and lateral 

 vessel, D' = connection to dorsal vessel, i' = connection to lateral vessel. 



JFigs. 1 and 3 were drawn from living animals compressed between slips of 

 glass. 2 and 4 from preserved specimens (Liquid of Kleinenberg, Borax-Carmine, 

 Xylol-Balsam). Drawings except Fig. 5 were made with Reichert's camera lucida 

 and lenses. 1 and 2 with oc. 4. obj. 3, 3 and 4 with oc. 4. obj. 2. 



Zoological Laboratory, University Glasgow. 



* Quart. Journ. Micr. Sc. Vol. XXV. Suppl. p. 68. 1885. 



5 Classen und Ordnungen des Thierreichs. 4. Bd. Nemertini p. 247. 1899. 



fi Niederländisches Arch. f. Zool. Bd. IV. 1. Hft. p. 10. 1877. see also v. 

 K ennel's article p. 339 and E. Blanchard second mémoire sur l'organisation des 

 Malacohdelhs. Ann. des sc. Nat. T. 12. 1849. p. 268—278. 



' Annot. Zool. Jap. Vol. I. p. 105—112. 



