The Microscope. 



Published on the 10th op Each Month, 



At 25 Washington Avenue, Detroit, Mich. 



All articles for publication, books for review and exchanges should be addressed to 

 the Editors of "The Microscope," 25 Washington Ave., Detroit, Mich. 



Subscriptions, Advertisements, and all business matters, are attended to by The 

 Microscope Publishino Co., 25 Washington Avenue, Detroit, Mich. 



No receipt will be sent for subscriptions received unless specially requested. 



Specimens for examination should be sent to the Microscope Laboratoi-y, 25 Washington 

 Avenue, Detroit, Michigan. In all cases the transportation charges on these specimens 

 must be prepaid, and special directions for packing and shipping will gladly be sent upon 

 application. 



Vol. VIII. DETROIT, NOVEMBER, 1888. No. 11 



ORIGINAL COMMUNICATIONS. 



THE FOKM AND SIZE OF THE RED BLOOD-CORPUSCLES 

 OF THE ADULT AND LARVAL LAMPREY 

 EELS OF CAYUGA LAKE.* f 



SIMON H. GAGE, B. S., 



A S the red blood-corpuscles of the camelidse form an exception 

 "*■ ^ in the great mammalian group in being oval instead of 

 circular in outline, and, according to Gulliver (3), J in not forming 

 distinct rouleaux or rolls, so the red corpuscles of the lamprey eels 

 form an exception in the great non-mammalian group of vertebrates 

 (birds, reptiles and fishes) in being bi-concave and circular, instead 

 of oval and biconvex, like those of all the other animals in this 

 great group. The corpuscles also agree with those of mammals in 

 forming distinct rouleaux. This is most marked in the brook 

 lamprey and the larva. In the 9 mm. embryo the corpuscles were 

 often seen in rolls of three or four in the circulating blood. (Fig. 

 E. F.) This has also been observed in the vessels of the dog's 

 mesentery (19). A nucleus is present in all the corpuscles, 

 but as it is small and placed in the thickest part of the corpuscle, it is 

 not apparent in the perfectly fresh corpuscles, except faintly in some 



* Following Jordan and Gilbert (Synopsis of the Fishes of North America, 1882), the 

 adult lampreys are called sea lamprey (Petromyzon marinus) and brook lamprey {Amnio- 

 ccstes branchialis). The name Ammoccetes was originally applied to the larval condition, 

 supposing it to be a distinct animal and not merely a larva. All the specimens from which 

 blood was taken were obtained in May and June in the streams flowing into the head of 

 Cayuga Lake. The smallest larvae (embryos 9 mm. long) were taken from the nest of the 

 sea lamprey. The larger larvas were dug out of a sand-bank along the stream; it is no 

 known whether they are the young of the sea or of the brook lamprey. 



+ Transactions American Society of Microscopists, 1888. 



± The numbers in parenthesis refer to the bibliography at the end of the paper. 



