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regard I refer to Meixner’s (1907, pp. 144—147) treatise on »die 
geographische Verbreitung der Stylochinen« and his conclusion: 
»So kommt es, dass nach unsern heutigen Kentnissen jede Kiisten- 
partie ihre besondere Stylochinen-Formen zu haben scheint«. His 
additional statement, „aus diesem Grunde ist mir neulich zweifel- 
haft geworden, ob ich recht getan håbe, den unzureichend beschrie- 
benen St. reticulatus Stps. aus dem Japanischen Meere mit der von 
mir beschriebenen Form von der Somaliktiste zu identifizieren«, 
can indeed be considered justified, for I might call to mind the 
faet that Yeri and Kaburaki (1918) have identified Stimpson’s 
„Stylochus reticulatus^^) as a Planocera = PI. reticulata Stimpson 
from Misaki, in full accordance with Lang 1884, p. 455. Here I 
may add that in a recent paper Dr. Frieda Meyer describes a 
Polyclad from Koseir in the Red Sea under the title Stylochus 
reticulatus Meixner? As far as I can gather from her description 
and figures, this form does not belong to Meixner’s species. She 
does not mention the occurrence of the characteristic pattern »aus 
umbrafarbenen Netzwerk« of the latter species, but notes only that 
the colour of the dorsal surface is „dunkelbraun“ and when the 
epidermis is removed, „hellbraun“. It would be too long to compare 
the two forms in detail here, but this mueh can be said that 
already the location of the mouth, near the end of the pharyngeal 
pocket, and the sexual pores speaks against an identification. 
According to the rules of nomenclature, the name reticulatus Meix¬ 
ner cannot be maintained, and I shall therefore substitute for it 
Stylochus meixneri n. nom. For Meyer’s species I might here propose 
the name St. coseirensis n. nom. 
Body-wall: It has already been mentioned in the case of 
Cryptophallus wahlbergi Bock 1913 that the epithelium is extremely 
rich as to giands, but lack of space has prevented any detailed 
information. In the species under consideration, the dorsal side has 
^) The identification of Stimpson’s species might] of course only be of 
more or less problematic nature. In the present case I might regard the 
undertaking of the Japanese authors as quite correct. In this connection I 
must warn against identifications founded solely upon poor verbal descriptions 
of animals from widely separated localities. Only the greatest caution in the 
determination is of value for a true knowledge of the geographical distribution 
of the species. 
