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Show 128 MR. W. E. HOYLE ON T H E [Mar. 5, enclosed by tbe hooded portion of the pen, and with the anterior end attached laterally to the posterior end of the csecal lobe of the stomach. The prostate gland, vesiculse seminales, and spermato-phore- sac are small; the efferent duct is long and slender, extending forward over and beyond the base of the left gill. ' XI. The Funnel-Organ. This apparatus has been the subject of one or two communications within the last few months, and hence it seemed desirable to make what contributions to the subject were possible from the material at hand. Its history may be dismissed in a few words, since Dr. Brock has recently gone into this matter somewhat fully **. It seems to have been first observed by Heinrich Muller2, who observed it in a large number of species during a sojourn at Messina in 1852. He describes the macroscopic appearance and gives some account of the minute structure. It consists of a median and two lateral pads. " Their surface," he says, " is made up entirely of spindle-shaped corpuscles They present great similarity to the nettle-organs of other animals, but are devoid of a filament . . . They are developed in the interior of cells, in which they are often twisted and coiled in various ways." No suggestion regarding their function is here propounded. Franz Boll3, in his classic " Vergleichende Histiologie des Mol-luskentypus," devotes a page to the consideration of the topic. He confirms Muller's account, and points out in addition that the fusiform corpuscles (which he figures) become surrounded by an excretory vesicle (" Secretblaschen " ) . He compares them with the rod-like bodies found in the epidermis of the Turbellaria, but makes no suggestion as to their proper function. In 1877 Bobretzky 4, in his finely illustrated work on the development of the Cephalopoda, figured sections of the organ in the embryos oi Loligo, and referred to it as a " thickening of the epidermis (? rudiment of the funnel-organ)." In 1881 Prof. A. E. Verrill5 described a very highly developed form of this apparatus in the cases of Taoniuspavo and T. hyperboreus. Shortly afterwards I was able to show that a similar structure is present in all the species of that genus 6, and, being at that time ignorant of the previous accounts of it, proposed to give it the name of " Verrill's Organ." In the light of our present knowledge it seems inappropriate to continue the use of this name, and perhaps the proper course to pursue would be to make use of the name funnel-organ ("Trichterorgan"), which occurs in the pages of the earliest writers upon it. 1 Nachrichten Gottingen, No. 17, 1888, 3 pp. 2 Zeitschr. f. wiss. Zool. iv. p. 339 (1853). 3 Arch. mikr. Anat. v. Suppl. p. 97 (1869). 4 Op. cit. figs. 52, 55, 57, 74, and especially 83. " Cephalopods of N.E. America, IL," Trans. Connect. Acad. v. pp. 413, 432, pi. Iv. figs. 2d, 4a. Loligopsis and other genera," Proc. Roy. Phys. Soc. Edinb. viii. 1885. |