OnCELLA. 389 



long by l"-0 in breadth at its base which is directed anteriorly. It is attached along 

 the external border of the lung from below the pericardial attachment and from the 

 anterior margin of its base. A process, 2 inches in length, is sent upwards along the 

 pericardium, and another process passes inwards under the pericardium as far as the 

 inferior vena cava on the right side. The said gland consists of two irregularly 

 shaped masses, one of which is applied to the internal margin of the lung, and has a 

 process prolonged upward from it along the pericardium as on the opposite side, and 

 the other lies internal to the former mass, and reaches to the side of the vena cava. 

 The portion of the gland which runs inwards towards the vena cava, and the 

 process prolonged up the pericardium are traversed by an enormous vein, which 

 when opened has a capacity of 0"9 inch throughout its course. The veins of the 

 two sides open by a common orifice into the right side of the inferior vena cava 

 immediately below where it reaches the heart. The left vein is thus twice as long 

 as that of the right side, and it arches slightly upwards near its termination, so that 

 its orifice is placed nearer the heart than that of the left side. The vessels, as they 

 bend round the base of the gland of the left side and traverse the double glandular 

 mass of the right lung, give off numerous fine branches to the glands, and, running 

 about two inches along the pericardium, they are found to proceed from the walls 

 of the chest, being projected off the sternal portion of the cavity on to the peri- 

 cardium. At this point they are in close relation with the internal mammary artery 

 (fig. 2, m.), which leaves the pericardium from the thoracic wall at the point where 

 they reach the latter structure. I never have had an opportunity of examining care- 

 fully the larger vascular plexuses wliich exist along the vertebral column of this 

 dolphin and in its intercostal spaces, but the origin of this large venous trunk from 

 the chest would render it probable that its chief function was to relieve the venous 

 plexuses by ajffiording their blood a short and direct channel to the heart, and thus a 

 more frequent flow than they would possess had the blood to travel a greater dis- 

 tance. The object of this would seem to be to confer great functional activity on 

 the respu'atory structures of the chest, which it is necessary should perform their 

 functions reliably, so to speak, and weU. 



Minute striwture of pulmonary glands. — In treating of the pulmonary organs 

 of Flatanista gangetica, I shall have occasion to pass under review certain 

 glandular structures analogous to those under consideration. In illustration of 

 the tissues in question, I have figured on Plate XXXVII, fig. 5, a portion of 

 the gland of Orcella, and at fig. 4 a part of that of Flatanista. These sections 

 drawn under a low microscopic power make obvious the resemblance of theh' 

 intimate structure. The main substance of the tissue is composed of a retiform 

 mesh- work (r.), in the interstices of which are closely packed cells (fig. 4, c.) of the 

 diameter and appearance of lymph corpuscles. The finer threads of connective 

 tissue in some places are as delicate as a spider's web, in others thicker, almost 

 membranous in consistence ; the two kinds forming a great variety in the dimen- 

 sions and figure of the areolae. Scattered about are much larger open spaces, quite 

 irreo-ular in contour and in tliickness of walls. These evidently are transverse 



