For comparison we have listed (Table 6) clutch-sizes for some other plethodontids. It should be noted that these numbers refer only to eggs deposited in clusters, and not to large ovarian eggs. Thus, _Aneides hardii_ has the lowest range in clutch-size of any North American plethodontid on record. It has been noted in other species that low clutch-size is correlated with low productivity, slow population turnover, and long average life-expectancy (Lack, 1954:103-105; Pitelka and Johnston, MS). If this is the case with this salamander, several other features in its environment and habits would tend to reinforce such population structure: the animals are exceedingly well-concealed (they were first described only 17 years ago [Taylor, 1941]), apparently have few natural enemies (one garter snake [_Thamnophis_] was collected within the habitat of the salamander in three years), apparently have few and benign parasites, and abundant and readily available food. Table 6.--Ranges and Mean Values of Clutch-sizes in Salamanders of the North American Plethodontidae[1] ========================================== | Range | Mean ---------------------------+-------+------ _Desmognathus_ spp.[2] | 11-40 | 20 _Leurognathus marmorata_ | 28 | _Plethodon cinereus_ | 3-13 | 9 _Plethodon_ spp. | 8-18 | 13 _Ensatina eschscholtzii_ | 12-14 | 13 _Hemidactylium scutatum_ | 30 | _Batrachoseps_ spp. | 7-74 | _Aneides hardii_[3] | 1-6 | 3.6 _Aneides_ spp. | 7-19 | 13 _Stereochilus marginatus_ | | 57 _Pseudotriton ruber_ | 72 | _Manculus quadridigitatus_ | 3-48 | ---------------------------+-------+------ [1] From Bishop (1947) and Stebbins (1951). [2] Clusters of one and two occasionally found in _D. ochrophaeus_. [3] This study, and from Lowe (1950). _Eggs and "incubation"_ Our information concerning eggs essentially duplicates that already reported (see Stebbins, 1951). All egg clusters that we found were in small chambers within decomposing fir logs. In each instance the eggs were suspended from the roofs of the chambers. The clutch of six eggs was a compact mass, and the individual suspensory cables of the eggs were intertwined and fused with one another. The clutches of four eggs, although they too were compact clusters, had each suspensory pedicel distinct from the others. The surface of the eggs was lightly moist, but did not glisten with water, and each egg was completely free of the others. The outer coat of jelly of the fresh eggs measured about 6.4 by 5.7 mm. as they hung suspended; sizes were uniform and no egg was notably smaller or larger than the others.