ADEENALS OF HiEMATOCRYA. 543 



new multinucleate cells. In old Pike this multiplication is 

 arrested : the connective tissue increases in quantity and density, 

 and the multinucleate cells are more separated from each other. 

 'Jlie connective tissue and the capsules whlcli it forms for the 

 adrenal and its subdivisions, are richly supplied with blood-vessels. 



The structure of the adrenals, however, is subject to great 

 variation within the limits of one and the same species in the 

 piscine class. The following modifications have been observed in 

 the Cod-fish ' : 1. Very rarely the adrenals are entirely absent. 

 2. They are semifluid, very vascular, not encased in a capsule, 

 and without defined form ; the blood-corpuscles are extremely 

 nmnerous, aggregated in small lumps, and in various stages of 

 transmutation. 3. They possess a proper capsule, being more or 

 less vascular. 4. They are shrunk, with but a few, or without 

 any blood-vessels. 5. Not rarely a part of an adrenal is composed 

 of cells and lobules, whilst another part is a formless conglomera- 

 tion of molecular particles, fat-globules, &c. 



Adrenals are entirely absent in the Herring and in the Launce 

 (^Ammodi/tes Tobianus). 



The fish-like Batrachia resemble some Fishes in the subdivided 

 condition of the adrenals ; twenty or more lobules, showing the 

 above-described structure, may be found partly imbedded in the 

 substance of the kidney, at its mesial border, partly between tlie 

 kidney and the renal and postcaval veins, surrounding the coats 

 of the eiferent veins (^Siren, Triton). In the Frog and Toad the 

 adrenals appear as a yellow streak on the sternal aspect of tlie 

 kidney, arching from about one line from the fore end to within 

 two lines of the hind end of the gland ; it shows a lobular struc- 

 ture, and surrounds the eiferent emulgent veins, closely adhering 

 to or imbedded in the coats, as they leave the kidney to join or 

 form the postcaval vein. The lobules consist of groups of multi- 

 nuclear cells, containing a greater proportion of oil-globules than 

 in Fishes : but both the free nuclei and granules are present, the 

 former sometimes showing stages of developement into nucleate 

 cells. The blood is supplied chiefly by branches of the reniportal 

 vein. 



In the Ophidia the adrenals are long, slender, lobulate bodies, 

 closely adherent to the coats of the emulgent veins, in advance of 

 the kidneys : in a Python of ten feet in length they measure 

 nearly one inch. The adrenals are rather less elongated in Anrjuis 

 fnujills. The adrenals are supplied by minute branches from the 



' cccsxxi. ' Fische,' p. 258. 



