Quain's elements of anatomy . ules. In this way, the whole gland ismade up, the number of its lobules and of the branches of its ductdepending on its size ; for whilst some glands of this Idnd, like the Q 2 228 SECEETIXG GLA^^DS. parotid, consist of innumerable lobules, connected by a large and many-branched duct, others, such as some of the sebaceous glands of the skin,are formed of but two or three ultimate lobules, or even of a single fact, a small racemose gland resembles a fragment of a larger one. The smallest lobules were originally called acini, a term which is nowgenerally used
Quain's elements of anatomy . ules. In this way, the whole gland ismade up, the number of its lobules and of the branches of its ductdepending on its size ; for whilst some glands of this Idnd, like the Q 2 228 SECEETIXG GLA^^DS. parotid, consist of innumerable lobules, connected by a large and many-branched duct, others, such as some of the sebaceous glands of the skin,are formed of but two or three ultimate lobules, or even of a single fact, a small racemose gland resembles a fragment of a larger one. The smallest lobules were originally called acini, a term which is nowgenerally used to denote the saccular recesses in the lobules. These arealso termed alveoli. The ultimate saccules of a racemose gland are lined, and some-times ahnost filled by the secreting cells, a cavity being left in thecentre communicating with the excretory duct (fig. 217). In some cases,minute canals lead from the central cavity between the cells, andthese may aid in the conveyance of the secretion of the latter into the Fig. Pig. 217.—Section of a kacemose gland, showing the cojimencement of a ducpIN the alveoli. Magnified diameters (E. A. S.). a, one of the alveoli, several of vvhicli are in the section shown grouijecl around thecommencement of the duct. Ci ; a, an alvcohis, not opened by the section ; b, basementmembrane in section ; c. interstitial connective tissue of the gland ; d, section of a ductwhich has passed awf// from the alveoli, and is now lined with characteristically-striatedcolumnar cells : s, semilunar group of darkly-stained cells at the periphery of an alveolus. cavity. It is doubtful whether these intercellular canals have properwalls or are merely formed by the juxtaposition of grooves on theadjacent sides of the cells. Further, the flattened cells which composethe basement-membrane may send delicate lamellar processes betweenthe alveolar cells, among which they form a sustentacular network (Boll,Ebner). Many glands, yielding very different secre
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