PLATE I. 

 *THE DEPOSITING OF THE EGG OF CHIMERA COLLIEI. 



(All figures about natural size.) 



ft. Anus. l.g. Lime gland. 



c. Crease in tumid eminence in median ventral line, m. Cord representing rudiment of dorsal mesentery, 



just posterior to opening of oviducts. Fig. 2. and containing the posterior mesenteric 



c. Crease in oviduct in which marginal web of vessels. 



capsule was laid down. Fig. 4. o. Ovary. 



c. a. Tumid eminences formed by prolapsed ends of op. Opening of oviducal sinus into cardinal sinus. 



oviducts. ovd. Oviduct. 



c. f. Capsular filament. ovd. a. Oviducal artery. 



c.o. Capsular organ of attachment. ovd. s. Oviducal sinus. 



c. s. Cardinal sinus. (Margin of. ) f. Urinary papilla. 



f. Funnel of oviduct. r. Folds at lower end of rectum. 



h. Heart. r. s. Receptaculum seminis. 

 /. Liver. 



Fig. i. Preparation of gravid female, showing eggs in oviduct. The egg-capsules are well formed, 

 the egg-containing portion situated in the hinder portion of the oviduct. The external 

 openings of the oviduct protrude from the body. The receptaculum seminis is shown at 

 r. s. The oviducts extend far forward ; their single opening appears at f., immediately 

 behind the position of the heart, h. The mesovarium is greatly restricted; it can, how- 

 ever, be distinguished on the left side of the figure where the capsular gland has been 

 drawn out. The oviducal artery is extremely conspicuous at this stage. 



Fig. 2. Region of ventral fins of a specimen which has recently deposited eggs, showing the pro- 

 lapsed ends of the oviducts. 



Fig. 3. Filamentous end of egg-capsule showing bulb-shaped organ of attachment. After sketch 

 by Professor Wilbur. 



Fig. 3 a. Filamentous end of similar capsule. 



Fig. 4. Preparation showing oviducts of a specimen about to deposit egg-capsules. The oviducts, 

 as shown in fig. i, pass back on either side from the median funnel, f. The one at the 

 right in the figure is shown lying in a capacious blood-filled sac of the peritoneum, ovd. s. 

 This sinus is slung from the dorsal wall of the body cavity : its sides (right and left) 

 draw closer together as they leave the oviduct and approach the (dorsal) wall of the 

 body cavity. And here appears finally a series of openings, op., through which blood of 

 the oviducal sinus obtains free communication with the cardinal sinus, c. s. It is evident, of 

 course, that the oviduct, ovd., is bathed in the blood contained in the sinus; and that it can 

 well be seen only where it lies against the wall of the sinus, the blood then forming the dark- 

 red masses at either side of the oviduct. The preparation has been made so that the 

 external opening of one oviduct is retained. From it one sees protruding the narrow 

 end of the egg-capsule. The opposite oviduct is shown opened. The details of the lime 

 gland appear at /. g. Immediately below it from a transverse fold in the oviduct arises 

 the viscid secretion, c. o., which draws together posteriorly and becomes the capsular 

 filament, c. f. One observes many creases in the wall of the oviduct. In the deepest, 

 c., the lateral web of the egg-capsule is laid down. The creases are especially note- 

 worthy near the hinder opening of the oviduct. Here its muscular walls serve to hold the 

 capsule as it hangs in the water while the remainder of the capsular filament is being devel- 

 oped. 



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