ASCARIS BICOLOE, 139 



provided with cuticular bands 0.024 broad, but without finer striae; the bands give a serrate appear- 

 ance to the margin of the worm, when seen under the microscope. Oesophagus consists of two por- 

 tions, an anterior and a posterior; oesophageal and intestinal caeca absent. 



Length (all females?) : 62 to 75'"""; breadth 2 to 2.5"'"'. 



Cotypes: British Museum and Coll. B. A. I. (U.S.N.M., No. 2824). 



Habitat : Stomach of marine mammals. 



Summary. — This supposed species from Tricheclms rosmarus {=Odobenus rosmarus) 

 should not be confused with "J^. hicolor Rudolphi, 1793," from Perea fluviatilis. A. 

 bicolor Baird was described in 1868 from specimens taken from a walrus; it has not 

 been reported since that time. We have examined several of Baird's originals, but 

 having no males we are unable to definitely place the worm, although we are somewhat 

 inclined to look upon it as identical with A. simplex. Murie, who collected the 

 nematodes, considered them to be the cause of death of a walrus he examined. The 

 worm is cited by von Linstow (1878) and Stossich (1896), but these authors did not 

 examine specimens. In detail the history of the parasite is as follows : 



Historical review.— As the original article by Murie and Baird has an impor- 

 tant medical as well as zoological bearing, we quote it here in full, with the original 

 illustrations : 



(1868.) . [p. 67.] 



4. On the Morbid Appearances observed in the Walrus lately living in the Society's Gardens. By James 



Murie, M. D., Prosector to the Zoological Society. With a Description of a New Species of Ascaris 



found in the Stomach. By Dr. Baird, F. L. S. 



In 1853 the society obtained a very young walrus (Tric]ieehu8 rosmarus, Linn.), which specimen 

 unfortunately only lived some few days after its arrival. From that time up to the' 1st of November 

 last (1867) no opportunity has offered of adding another example of this exceedingly interesting animal 

 to the collection. When, therefore, a tolerably well-developed, although still young, male sea horse 

 was reported to have arrived safely in the gardens, the curiosity of the members of the society and the 

 public generally naturally was aroused. Notwithstanding the inclemency of the weather the number 

 of visitors was great. 



The proper food of a walrus in a state of nature has been variously stated by different naturalists. 

 Some assert it to be a vegetable eater ; others believe it to be entirely carniverous, while a third notion 

 has gained ground that i t may occasionally partake of food of the one kind or the other. 



Our superintendent, therefore, under these circumstances, felt a difficulty in deciding what might 

 be the best food to giyethe creature so as to retain it in as good health as possible. The results of his 

 experimenlis concerning suitable diet he has himself laid before the society's meetings on a previous 

 occasion. I shall just reiterate his conclusions, namely: It refused every kind of seaweed offered, but 

 it greedily gulped up the soft bodies of Mya truncata and M. arenaria, which were its printjipal food, 

 besides quantities of whelks, mussels, fish cut up in small strips, and the viscera of fish; these last, 

 however, having previously been well washed and cleaned. 



It may be remarked that the youug walrus dissected by Professor Owen in 1853 had been fed during 

 its captivity on oatmeal, milk, and Wiiter. The specimen at present under consideration, when first cap- 

 tured, and on shipboard, had also received a certain allowance of the above, along with strips of fat pork. 



I have taken notice of the animal's food for the purpose of directing attention to the question, 

 whence were the ova of the entozoa obtained that ultimately led to the walrus's death? 



At the period of arrival in the gardens the walrus looked thin and lean. There was an amount 

 of loose skin, however, which indicated that better regimen than that which he had lately been under 

 would soon render the body plump and comparatively free from the very numerous skin folds. These 

 wrinkles, it may be observed, in several places met each other, so as to form a series of elongated 

 diamond-shaped inclosures. 



