198 BULLETIN: MUSEUM OF COMPAEATIVE ZOOLOGY. 



and Paguridse by Cuenot ('87, p. xlv), but were considered as of a 

 lymphatic nature. In his later and more complete work Cuenot ('91, 

 pp. 76-80) describes these glands in several Decapods as found between 

 the two branchial blood channels (Crabs and Pagurus), or as closely 

 investing the walls of either the efferent vessels (Palsemon), or of 

 the afferent vessels. He still ascribes to them lymphatic functions, and 

 makes no mention of Kowalevsky's paper, which had appeared two years 

 before. 



Kowalevsky ('89) studied these organs from a physiological point of 

 view. He found (pp. 35-42) that by intra vitam injection of a one per 

 cent solution of ammonium carminate into the body spaces of Astacus, 

 the endsac of the antennal gland soon became red. If indigo-carmine be 

 injected, the labyrinth becomes colored blue, but the endsac remains un- 

 colored; and if a thorough mixture of these two pigments be used, the 

 endsac and labyrinth rigidly select the colors. Injection of tincture of 

 litmus gave reactions showing the endsac to be acid, the labyrinth in 

 part alkaline and in part neutral. Palsemon yielded almost identical 

 results, as far as regards the antennal glands, but in addition there were 

 produced by the injection of tincture of litmus two red streaks in each 

 gill, one on each side of the shaft. There were eight double streaks on 

 each side of the body, viz. on the five gills and the appendages of the 

 three maxillipeds. This coloration was caused by rows of cells in which 

 were the same color appearances as in the cells of the endsac of the 

 antennal glands. Further, these cells acted toward the mixture of am- 

 monium carminate and indigo-carmine precisely as did the cells of the 

 endsac, from which it is to be inferred that there is in each gill tissue of 

 the same function as that of the endsac. These glandular regions are the 

 so called branchial glands. 



The purely physiological work of Kowalevsky was supplemented by 

 Allen ('92, p. 79), who describes the structures of these glands in the 

 gills of Palaemonetes. They are spherical and composed of conical cells, 

 the apices of which border a central area. There are two varieties of 

 the gland cells, somewhat different in shape and in position. Allen ten- 

 tatively considers these spherical branchial glands as belonging to the 

 series of ectodermal glands. It should, however, be noticed that, ac- 

 cording to Cuenot and Kowalevsky these glands agree in function with 

 the mesodermic portion of the antennal glands. 



The description and figures given by Allen strongly remind one of the 

 tegumental glands described by Hcrrick ('95, p. 125, Plates A and 49) 

 from the pleopods of the female Homarus, the function of which is the 



