. The Danish Ingolf-expedition. Marine animals -- Arctic regions; Scientific expeditions; Arctic regions. 94 MEDUSAE. I. figures found by the measuremeuts. — It will be observed that the number of tentacles varies fairly considerably within one and the same group of size; thus in specimens, 16—20 mm wide, there may be 38—58 tentacles. Each of the radial canals carries only one gonad, completely encircling the canal without leav- ing a ventral edge free. This will be seen from the 16 and 17, representing transversal sections of male and female gonads. The section of the female gona
. The Danish Ingolf-expedition. Marine animals -- Arctic regions; Scientific expeditions; Arctic regions. 94 MEDUSAE. I. figures found by the measuremeuts. — It will be observed that the number of tentacles varies fairly considerably within one and the same group of size; thus in specimens, 16—20 mm wide, there may be 38—58 tentacles. Each of the radial canals carries only one gonad, completely encircling the canal without leav- ing a ventral edge free. This will be seen from the 16 and 17, representing transversal sections of male and female gonads. The section of the female gonad shows that the eggs are first developed in the middle part on both sides, whereas small, immature eggs are still present in the dorsal and ventral parts. From the Faeroe Islands we possess a number of young speci- mens. In the smallest specimens (diameter i—5 mm) the gonads are spherical and placed near the middle of the radial canals; in a .spe- cimen 7 mm wide the gonads (female) are oval, about i'/^ mm long; in the largest specimen (diam. 10 mm) they are elongate, 2 mm long. In all specimens from Iceland the gonads are linear. Their , . , length in relation to the length of the radial canals varies from '/, raclial canal with mature male gonads. ' — Fig. 17. Phiaiidium hemisphariciim to nearly 3/ but stauds in correlation to the developmental stage of (Gronovius). Transversal section through ir o radial canal with female gonads. the individual, as will be Seen from table XII. This table represents the correlation between the diameter of the individuals and the relative length of the gonads (i. e. the relation between the length of the gonads and that of the radial canals, expressed by means of the. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Danish Ingolf-Expedition (1895-1896); København
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Keywords: ., bookcentury1800, bookdecade1890, booksu, booksubjectarcticregions
