414 Miscellaneous. 



I thought of an equivalent to the lateral organs of Rhipidoglossa, 

 but then noticed that the organ was present only in the foremost 

 portion of the lateral mantle- chamber, and I therefore assumed that 

 a connexion existed with the rudimentary gills or organs of Spengel. 

 The mode of preservation of the animal under investigation was not 

 such as to enable a clear idea of the innervation to be obtained, and 

 therefore in a figure of Paflmlla deaurata recently published with 

 another object (" Beitrage zur Kenntnis der Mollusken. — 1. Ueber 

 das Epipodium," Zoitschr. f. wiss. Zool. 53 Bd., Taf. xxiii. fig. 3), 

 which shows a thickened streak at the spot indicated, I bad desig- 

 nated this simply as " sense-organ " (" Sinnesorgan "). 



A short time ago T received some well-preserved specimens of 

 Patina jyellucida from Heligoland, and in a series of sections I have 

 found the sense-organ again very distinctly, and have determined its 

 innervation. The nerve, which runs beneath the streak of sensory 

 epithelium, proceeds from the olfactory ganglion of Spengel ; it is 

 on the whole feebly developed and not altogether easy to distinguish 

 between the fibres of the retractor muscle, though most distinct in 

 front. The epithelial band is fairly broad at the spot where it 

 encircles the retractors in front ; from this point it becomes still 

 broader towards the middle, and the cells become flatter, while at 

 the outer side it soon narrows considerably, while the columnar 

 cells diverge fan-wise ; at this spot it differs most from the sur- 

 rounding epithelium, though the entire streak exhibits the charac- 

 teristics of sensory epithelium in a well-marked degree. 



With reference to the dissemination of this organ, it may be 

 remarked that it is possible that it occurs in all Patellida?, excluding 

 Acma^a and Lejjeta, since I have traced it in Patella cm'ulea in 

 sections and have seen it macroscopically in Patinella, two forms 

 which are not far distant from the terminal points of the phyletic 

 developmental series. 



Neither Spengel (" Die Geruchsorgane und das Nervensystcm von 

 Mollusken," Zeitschr. f. wiss. Zool. 35 Bd.) nor Bernard (" Orgaues 

 palleaux des Prosobranches,'' Ann. Sc. Nat. vii. 9), who has recently 

 minutely investigated the branchial sense-organs of the Proso- 

 branchia, have noticed this prolongation of them at the sides of the 

 body in Patellida:', but have only observed the portion which is in 

 immediate connexion with the nuchal papillas, the rudiments of the 

 Zygobranch gills. Bernard even expressly states with regard to 

 Patina lyeUvcida that " the organ of Spengel is situated entirely 

 behind the ganglion." The course of the organ as described above 

 appears to me to be not without importance, and I therefore wished 

 to give a provisional account of the fact ; I shall revert to it later on 

 in greater detail. — Zooloqisclier Anzeiger, xvi. Jahrg., no. 412 

 (February 13, 1893), pp. 49, 50. 



071 Cirripedes and otlier Crnstaceans commensal ivitli Mediterranean 

 Turtles. By MM. E. Cheveeux and J. de Gueene. 



It is seldom that the opportunity is presented to zoologists of 

 observing the pelagic Vertebrates at sea under the normal con- 

 ditions of their existence. Accordingly on board the ' Hirondelle,' 



