Das System der Polycladen. 459 



Ganzen ist die Zahl und Lage der Augen je nach der Grösse und dem Alter der Thiere eine 

 beträchtlich verschiedene. 



Im anatomischen Bau und in der Art der Bewegung stimmt Stylochoplana palmula 

 völlig mit St. agilis überein. 



Fundort. Auf Posidonien am Posillipo, bei Nisida und auf der Secca di Benda Pa- 

 lumma. Wegen der Durchsichtigkeit und der Färbung des Körpers sehr schwer aufzufinden. 



30. Stylochoplana maculata Stimpson. 



? Planaria subauriculata'), Johnston J836. 30. pag. 16 u. 17. Fig. 2 «, ft, c im Text. — 

 JoHNSTON 1845. 45. pag. 436. 



Stylochus maculatus^), Quatrefages 1845. 43. pag. 14-1. Tab 4. Fig. 3. 3 a. Tab. 6. 

 Fig. 2. — DiEsiNG 1850. 56. pag. 217. — Diesixg 1862. 89. pag. 568. — '"jClaparede 1863. 

 93. pag. 20—22. Taf. IV. Fig 5—7. 



Leptoplana subauriculata, Uiesing 1850. 56. pag. 195. — ^j Maitland 1851. 65. — 

 Diesing 1862. 89. pag. 527. — ") Ray-Lankester 1866. 98. pag. 388. — ') Mac Intosh 1874. 

 110 (und 111). pag. 150. 



? Planaria corniculata ^) , Dalyell 1853. 68. pag. 101. Tab. XIV. Fig. 5. 6. 7. 8. 



Stylochoplana maculata, Stimpson 1857. 78. pag. 4. 



Planocera vel Stylochus corniculatus, Leuckart nee Stimpson 1859. 81. pag. 183. 



Stylochus ? corniculatus, Diesing 1862. 89. pag. 571. 



Stylochus maculatus ?*), Claparede 1864. 94. pag. 464. Ontog. 



Leptoplana subauriculata Johnst. = Planaria corniculata Dalyell, Johnston 1865. 96. 

 pag. 6. 



1) jiTlie animal, wheii fully exteiided, is about six lines long, and two broad, obtuse in front and ta- 

 pered behind; thus assuming a lanceolate or tongue-shaped iigure, veiy thin, flat, smooth, and of a pale or 

 wood-brown colour, witb some niilkwldte spots scattered over the back. Towards the anterior end we 

 perceive numerous small black eyes, or specks, collected into two irregulär parcels with a transparent space 

 between tliem; the eyes themselves are placed about and witliin a small circular transparent spot on eaeh 

 side, which is changeable in appearance, and bas some times the look of a small fold, or auricle, as is re- 

 presented in figure (3. The body is transparent enough to allow us to perceive that there are no defined 

 Organs, or vessels, beyond the proboscis, which is situated about the middle, and opens on the ventral sur- 

 face; the interior appears to be entirely composed of gelatinous globules, separated into compartments by 

 clear lines, which run from the centre to the pellucid margiii in an imperfectly radiating manner. — Pla- 

 naria subaur. is a marine species, and was found on a leaf of a young specimen of Laminaria saccharina 

 growing near the lowest tide-mark. Kept in seawater, it seemed to sicken sooner than most of its tribe, 

 Uving with me little better than two days; and although the water had not been changed, yet the coolness 

 of the weatlier had preserved it from putridity. Its motion was, in general, very rapid; and so smooth^ 

 continuous, and even, and made without the slightest apparent effort, that it reminded one of the noiseless 

 lapse of time : but occasionally the worm would behave itself very unseemly . rolling itself up until head 

 and tail met; then unbending, and tossing up and down the tail, as if annoyed by some pest pf wbich it 

 wished thus to rid itself.« 



Habit. Berwick Bay. 



58* 



