. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 42 EDGAR DAVIDSON CONGDON. constituting the spadix wall are in contact with the egg at one end since the spadix lies directly against the egg membrane. At their other end they extend for varying distances into the lumen producing a folded surface not unlike a digestive epi- thelium. It is probable that this large free surface is important in augmenting the absorption of food which is passed on to the egg (Fig- n)- Two views have obtained as to the way in which the hydroid egg takes up the cells. Balfour's text-book of embryo
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 42 EDGAR DAVIDSON CONGDON. constituting the spadix wall are in contact with the egg at one end since the spadix lies directly against the egg membrane. At their other end they extend for varying distances into the lumen producing a folded surface not unlike a digestive epi- thelium. It is probable that this large free surface is important in augmenting the absorption of food which is passed on to the egg (Fig- n)- Two views have obtained as to the way in which the hydroid egg takes up the cells. Balfour's text-book of embryology, pub- ^iV;&' c$' •::^:-;-vw^ ®® ^ w *(i' ?; '. ^? ^----^^--vT'i Ji^1"^ FIG. ii. lishecl in 1879, states that they are amoeboid and do so by putting up pseudopodia. Metchinkoff in 1887 described such a method in some medusae. Tichomiroff in the same year found a condi- tion in certain hydroid eggs which he terms an " amceboides ; Smallwood, '99, saw indications of amceboid activities in the egg of Pcnnaria tiarclla. A different conception as to the process of absorption is found in Doflein's account, '96, of the development of the egg of Titbn- larin larynx. It is apparent from his discussion that he has studied the question carefully. He concludes that although eggs have processes like pseudopodia, there is no amoeboid movement. Absorption occurs by the breaking down of the walls of the egg and adjacent cells to form a syncytium-like structure. When 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 Marine Biological Laboratory (Woods Hole, Mass. ); Marine Biological Laboratory (Woods Hole, Mass. ). Annual report 1907/08-1952; Lillie, Frank Rattray, 1870-1947; Moore, Carl Richard, 1892-; Redfield, Alfred Clarence, 1890-1983. Woods Hole, Mass. : Marine Biological Laborato
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
