NOTES ON A NEW LAND PLANARIAN. 115 
surface of the head. Further description of the distribution of the 
rhabdites in the horseshoe-shaped depression of the head will be 
given later in connection with the sensory and the glandular margins. 
Among the various epidermal glands, the erythrophile and the 
marginal glands need only be referred to here, as the others have 
less direct relation to the classification. The erythrophile glands 
(Plate IV., fig. 5, ep) are in this species uniformly distributed over 
the entire surface, though they are a little more densely aggregated 
in the sole-epithelium. They are readily recognized by their 
coarse granular contents, which have a strong affinity for eosin 
stains. The presence of the erythrophile glands and the chondro- 
cysts in the epidermis seems to preclude any direct generic 
relationship of the present form to Platydemus, in which the two 
structures art completely absent. 
The marginal glands in this species are well developed, and have 
their openings on the glandular ridges and on the glandular margins. 
Their posterior limit is about on the same level as that of the 
ovaries, being about 3°5 mm. from the head-tip. The glands are 
very large and long, reaching nearly to the brain or the lateral 
nerve cords and the gut (Plate IV., figs. 6 and 8, mg). They have 
an extremely oblique course from behind forwards, except at the 
head-apex, where they run directly downwards to open on the 
prominent ridge of this region (see Plate IV., fig. 6). The present 
species is peculiar in having both the erythrophile and the marginal 
glands, since, according to von Graff, these two glands rarely occur 
together in the land planarians. Hence he states that “im Allge- 
meine en erythrophile Kornerdriisen der Haut und Kantendrtsen 
einander ausschliessen scheinen, da es nur zwei Formen giebt, bei 
welchen beide zusammengefunden werden. Es sind dies Dolicho- 
plana feildent und Polycladus gayi, doch kann ich wenigstens von 
letzter Species bestimmt angesehen, dass die Kantendriisen derselb- 
en gar nicht den Charakter der Kantendriisen der iibrigen Land- 
planarien an sich tragen, sondern sich mehr als eine lokale Anhauf- 
ung von birnférmigen erythrophile Drisen darstellen. Es liegt 
dem nach hier derselbe Fall vor wie bei Rhynchodemus terrestris, wo 
in der Umgebung der Sinneskante—also an der Stelle pflegen— 
eine dichtere Anhaufung erythrophile Kornerdriisen zu beobachten 
ist.”’* It may be mentioned here that the present species is only 
remotely related to the genus Dolichoplana, since it lacks the 
important generic character of having the longitudinal parenchyme 
muscles developed only on the ventral side of the body. Von 
Graff’s view of the relation between the erythrephile and the mar- 
ginal glands may explain the nature of another kind of marginal 
glands which are found in the present species on the inner or ventral 
border of the glandular ridge (see Plate IV., fig. 8, mg). These 
* Von Graff, op. cit., p. 66. 
