490
JOHN E. CUSHINC
be taken in interpreting the results of field observations in the absence
of genetic data. This care should include the use of a number of reagents
and consideration of sex, size, and gene frequency relationship, as well,
of course, as the practice of a general alertness for the unexpected appearance of ecological and other complications [cf. further discussion in de
Ligny ( 1969) 1.
The most ideal situation for the study of blood groups in fish is, of
course, where genetic data can br obtained directly. A number of investigators have or are taking advantage of the possibilities offcred in
such species [see, for example, Sanders and Wright (1962), Ridgway
et al. ( 1966), the ictalurid (catfish) research and that on plaice of de
Ligny (1969) referred to above]. The potential usefulness for genetic
studies of some wild populations that cannot be cultured is illustrated
by the demonstration of Sindermann and Mairs (1961) that the spiny
dogfish shark, Squalus acanthias, like the brown bullhead, has a blood
group system with isoantibody correlates similar to the human ABO
system. This species is particularly valuable since it is viviparous and also
may be indicative of similar systems to be found in other elasmobranchs.
Attention is called, in closing, to some additional studies on fish blood
groups recently published. One shows the potential value of blood groups
for evolutionary and distributional studies of golden trout ( Calaprice
and Cushing, 1967), the other, an application of a useful and simplified
technique (Ridgway et al., 1958) for comparing erythrocyte antigenic
variability among different fish populations (Utter et al., 1966). The
technique was employed in this case in the evaluation of the relative
degree of inbreeding in Lahontan trout, Salmo clurkii henshawi, populations. The paper of Kilambi et al. (1965) applies this technique in the
differentiation of spawning populations of surf smelt, Hypomesus
pretiosus.
VI. CYCLOSTOMES
This class of vertebrates requires special consideration for the reason
that Good and his associates have developed the hypothesis that adaptive
immunity evolved within this phylogenetic level of organization. Reasons
for believing this are discussed by them in “Phylogeny of Immunity”
(Good et al., 1966) and elsewhere. These are based on the demonstration
that the lamprey, Petromyzon marinus (cf. also Pollara et al., 1966; Boffa
et al., 1967; Marchalonis and Edelman, 1968), possesses a set of immunological responses that fulfills the criteria for adaptive immunity and leads
JOHN E. CUSHINC
be taken in interpreting the results of field observations in the absence
of genetic data. This care should include the use of a number of reagents
and consideration of sex, size, and gene frequency relationship, as well,
of course, as the practice of a general alertness for the unexpected appearance of ecological and other complications [cf. further discussion in de
Ligny ( 1969) 1.
The most ideal situation for the study of blood groups in fish is, of
course, where genetic data can br obtained directly. A number of investigators have or are taking advantage of the possibilities offcred in
such species [see, for example, Sanders and Wright (1962), Ridgway
et al. ( 1966), the ictalurid (catfish) research and that on plaice of de
Ligny (1969) referred to above]. The potential usefulness for genetic
studies of some wild populations that cannot be cultured is illustrated
by the demonstration of Sindermann and Mairs (1961) that the spiny
dogfish shark, Squalus acanthias, like the brown bullhead, has a blood
group system with isoantibody correlates similar to the human ABO
system. This species is particularly valuable since it is viviparous and also
may be indicative of similar systems to be found in other elasmobranchs.
Attention is called, in closing, to some additional studies on fish blood
groups recently published. One shows the potential value of blood groups
for evolutionary and distributional studies of golden trout ( Calaprice
and Cushing, 1967), the other, an application of a useful and simplified
technique (Ridgway et al., 1958) for comparing erythrocyte antigenic
variability among different fish populations (Utter et al., 1966). The
technique was employed in this case in the evaluation of the relative
degree of inbreeding in Lahontan trout, Salmo clurkii henshawi, populations. The paper of Kilambi et al. (1965) applies this technique in the
differentiation of spawning populations of surf smelt, Hypomesus
pretiosus.
VI. CYCLOSTOMES
This class of vertebrates requires special consideration for the reason
that Good and his associates have developed the hypothesis that adaptive
immunity evolved within this phylogenetic level of organization. Reasons
for believing this are discussed by them in “Phylogeny of Immunity”
(Good et al., 1966) and elsewhere. These are based on the demonstration
that the lamprey, Petromyzon marinus (cf. also Pollara et al., 1966; Boffa
et al., 1967; Marchalonis and Edelman, 1968), possesses a set of immunological responses that fulfills the criteria for adaptive immunity and leads