MOLOTHRUS PECORIS, COW-BIRD. 181 



There is no doubt whatever that the Frhif/ilJa amMgna of Nuttall. yvhich AiWubou 

 once* hastily surmised to he a young Wliitc-crowned i?parrow, is nothing but a very 

 young Cow-bird, as questioniugly suggested by Baird. X newly-leathered bird in my 

 cabinet, shotiu the middle of July, at Washington, answers" perfectly to Nuttall's 

 description. 



Parasitism, iu the zoological sense of the term a frequent condition 

 of lower forms of life, is sufficiently rare among higher animals to excite 

 special interest; and the exceptional absence of the strong parental 

 instincts of birds is particularly noteworthy. Considering that con- 

 scious volition — that choice, in a word — determines the whole process 

 of perpetuation of the species in the Cow-bird, denying all but the 

 purely sexual of conjugal relations, abrogating parental relations, and 

 rendering family relations impossible, we must concede a case of para- 

 sitism having almost an ethical signiticance, to such an extreme is it 

 pushed. Certain low organisms, like the Entozoa^ for example, only 

 exist under conditions fulfilled within the bodies of higher animals, 

 presenting a (;ase not so widely different from that exhibited in the rela- 

 tion between a plant-germ and the soil in which it grows; but they 

 work detriment to their host, and even its death, by the irritation of 

 their presence in myriads, or their actual consumption of substance, and 

 in this respect are more exactly comparable to the true epiphytes, like 

 the mistletoe, drawing sap directly from the other plants upon which 

 they fix. Another kind of parasitism is illustrated by numerous insects, 

 sometimes designated as i^juoa, which are independent organisms, self- 

 supporting, yet habitually seeking to live upon other aninjals. Such 

 answer more nearly to the peculiar signification of a parasite, in its ety- 

 mological sense of an " uninvited guest," than the Entozoa do. and lead 

 up to cases of ])arasitism in its literal signification. Among mammals 

 we have i)ure parasitism in the asserted relations of the jackal and lion, 

 the former being literally "beside the table" of the latter. The Jaegers 

 are similarly and more forcibly parasitic, feeding at the expense and to 

 the annoyance of Gulls; so are some Gulls, in their turn, i)arasites of 

 the Pelicans, i)icking small fry out of the very beak of these industrious 

 fishers. The Bald Eagle is a bold parasite of the Osprey, accomplish- 

 ing by violence what is usually done by intrigue. But all such cases 

 relate simply to procuring of food; only a lew extremely "advanced 

 thinkers" among birds and the human species dispense with family ties, 

 duties, and delights, throwing the burthensome results of their sexual 

 propensities upon society. It is not difficult to trace, in either case, the 

 demoralizing effect upon the individuals themselves, or the mischief 

 wrought at large. But it may be straining an analogy to comi)are cases, 

 however similar, in one of which resides a moral quality which we n)ust 

 presume to be absent in the other. 



However this may be, it is singular that this particular kind of para- 

 sitism should occur in the isolated cases of birds so unlike, as Cuckoos 

 and Cowbirds, and only there, so far as we know. The egg of the Cow- 

 bird is less than an inch long, by about two-thirds of an inch wide; it 

 varies a great deal in size, as is seen on comparing- any large series. 

 Given tln^ existence of the habit of laying in other birds' nests, wc 

 should iiave anticipated its occuirence throughout some p;irticul;u 

 group, rather than its seemingly "sporadic" character. But there are 

 uo accidents in the order of nature ; if we could but see far enough, not 



* 8"° od. ill, 159. But later (iv, 20) he says that the young Cow-bird from wliich ho 

 made liis drawing was sent to him l)y Nuttall, and thar'lt was the Mine xpirimcii as that 

 descrii)ed by Niittall as the "Ambiguou.s Sparrow"—" nothing else than a young Cow- 

 peu-bird, scarcely Hedged." 



