. A text-book of invertebrate morphology. Invertebrates. 462 INVERTEBRATE MORPHOLOGY. however, possessing any ganglionic enlargement whicli can be termed a cerebrum. Various nerves are given off from the mass, two of which extend backwards throughout nearly the entire length of the body. The only sense-organs pres- ent are a number of small papillae on the anterior portion of the body, which are probably tactile in function. Glandular organs are highly developed. Scattered over the surface of the body are numerous flask-shaped glands, apparently ectodermal in origin, while lying in the ccelom
. A text-book of invertebrate morphology. Invertebrates. 462 INVERTEBRATE MORPHOLOGY. however, possessing any ganglionic enlargement whicli can be termed a cerebrum. Various nerves are given off from the mass, two of which extend backwards throughout nearly the entire length of the body. The only sense-organs pres- ent are a number of small papillae on the anterior portion of the body, which are probably tactile in function. Glandular organs are highly developed. Scattered over the surface of the body are numerous flask-shaped glands, apparently ectodermal in origin, while lying in the ccelom on each side of the mid-gut and extending back almost to the posterior end of the body are two long csecal tubes, a glan- dular structure being also connected with them anteriorly. These glands open in the vicinity of the hooks and have hence been termed the hook-glands (Fig. 211, Tig), and it has been suggested that they secrete a fluid which serves to keep the blood which the parasite ingests from coagulating, being thus similar to the glands in the pharynx of the Leeches. ng IS Fig. 313.—Diagram op Stkucture of Fbmalb Pentastomum (after Spenbcb). go = genital orifice. od = oviduct. hg = hooli-gland. ov = ovary. i = intestine. rs = seminal receptacle. ng = nerve-ganglion. ui = uterus. which serve the same purpose. Unless the ectodermal glands are excretory, no special organs for the carrying on of that function occur. The Peutastomidse are bisexual, the male being smaller than the female, and recognizable by the situation of the geni- tal orifice (Fig- 211, go), which is near the anterior end of the body, while in the female it is near the posterior end. The ovary and both unpaired organs situated beneath the dorsal surface of the body and extending almost its entire length. Anteriorly a pair of oviducts (Fig. 212, od) arise from the extremity of the ovary (ov) and pass downwards and. Please note that these images are extracted from scanned page images that may h
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Keywords: ., bookcentury1800, bookdecade1890, bookpublishernewyo, bookyear1894
