Albinism is not uncommon among wild flowers in Mount Rainier National Park. During the summer season of 1934, albino blossoms of the following were reported: Blue Lupine (Lupinus latifolius and L. volcanicus), Blue Gentian (G. calycosa), Indian Paintbrush (Castilleja miniata and C. oreopola) and Butterfly-tongue Lousewort (Pedicularis groenlandica).
Numerous albino blossoms have been reported in past seasons including, in addition to those mentioned above, those of the Red Mimulus (Mimulus lewisii), (Nature Notes, 9/3/1924 - Macy), Jacob's Ladder (Polemonium elegans) and Red Heather (Phyllodoce empetriformis), (Nature Notes, 8/8/1927 - Schmoe). In the case of one albino mimulus the same plant apparently was observed to be so characterized on two successive seasons. An albino gentian has been observed on Mazama Ridge for three successive seasons (Brockman). Such abnormal flowers have been reported from many places in the Hudsonian Zone of this park, indicating a wide distribution of albinos between 4500 and 6500 feet on Mt. Rainier.
The fundamental principles involved in albinism are fairly well understood. It is believed that sudden changes may take place in the form or color of an organism through some change in a definite unit of the reproductive material from which it originated. (DeVries mutation theory) Thus an abnormality in the germ-plasm of the parents results in abnormality of the offspring. In plants, such things as albinism, multiple rows of petals, seedlessness, thornlessness, etc., may be explained in that manner. Since these mutations were shown to reproduce themselves or "breed true", DeVries felt that this was proof that they originated in abnormalities of the germ-plasm of the parents. Thus, assuming a germinal change, an albino plant might be expected to reproduce this character as long as it was either self-fertilized or cross-fertilized with another albino evolved in a similar manner. This may be considered as an explanation for some of the albino flowers found in Mount Rainier National Park. Of course a perennial albino plant develops white flowers year after year throughout its life.
Schmoe, in reporting the albino red heather, states that only the blossoms upon one branch of the plant were white. This is known as a "sport". Such a character is not brought about by an abnormality of the germ-plasm of the parents. It had its origin in the body tissues of the plant during its growth. Such "sports" may be perpetuated only by means of vegetative propogation of the affected portion of the plant itself which, in the case of the red heather, would probably never occur naturally. An example of this type of mutation is the seedless grapefruit. It was propogated vegetatively by man by grafting portions of the original "sport" upon normal grapefruit stocks.
Many plants are not normally self-fertilized or "selfed". In the majority of cases cross-pollinization is the rule. The offspring of such unions contain the characteristics of both parents together with those of their ancestors. Many of these characteristics are not evident in the offspring - are subdued or are "recessive". Those that are evident are known as "dominant". If the pollen produced by a blossom of normal color is carried to the pistil of an albino (developed through a mutation in a single factor of the germ-plasm) the seeds produced would contain both the element for albinism and normal color in equal proportions or "dosages". However plants grown from this seed would all be normally colored because the character for color is dominant. Now if these normally colored blossoms, just described, are self-fertilized the seeds re sulting from such a union would produce some albino plants and some normally colored ones; the ration being three normal to one albino. This is known as segregation.
It is quite evident that the matter of albinism is by no means simple. Evidence to the effect that not all albinos are caused through strict mutations, but in many cases through crossing of mutants with normal blossoms is found in what might be termed "dilutants" - intermediate stages between the normally colored blossom and the albino due to incomplete dominance of the normal color. Examples of this have been especially noticeable in the lupine, individuals having been found representing almost the entire color range from pale pink to deep violet. In addition Blue Gentians of an old rose shade have been noted in close proximity to plants with albino blossoms. The presences of such variants has not been definitely linked with the albinos in so far as the flowers of Mt. Rainier are concerned. To establish their origin definitely will require considerable further study.
The observed albinos, then, may be classed as to their immediate origin. The majority develop through a sudden mutation brought about by an alteration in the germ-plasm of the parent, or through segregation following cross-pollinization in which a mutant is one parent.
Another class (i. e. the Red Heather) is the "sport".
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