. Bulletin of the Southern California Academy of Sciences. Science; Natural history; Natural history. The finding of an egg ball with a hole in it does not prove that the spiders have issued. If the ball is heavy it is probably parasitized. Of the 38 balls, 26 were unparasitized, while 9 yielded Baeus californicus (), and 2 Pseiidogaurax signata (), a total of parasitism of balls. But the parasitism within a ball is not necessarily complete. The Pseiidogaurax fly oviposits on the outside, and the larvae must penetrate the egg ball and consume the eggs; in one case 11 flies, and
. Bulletin of the Southern California Academy of Sciences. Science; Natural history; Natural history. The finding of an egg ball with a hole in it does not prove that the spiders have issued. If the ball is heavy it is probably parasitized. Of the 38 balls, 26 were unparasitized, while 9 yielded Baeus californicus (), and 2 Pseiidogaurax signata (), a total of parasitism of balls. But the parasitism within a ball is not necessarily complete. The Pseiidogaurax fly oviposits on the outside, and the larvae must penetrate the egg ball and consume the eggs; in one case 11 flies, and in the other 28 issued, but the evidences showed that many spiders also issued, and I calculated less than 50% parasitism. The Baeus has a better record, as we obtained in the cases counted 401 out of 403 (); 278 (100%); 207 (100%); 236 (100%); 396 out of 408 (); 274 out of 27'9 (); 232 out of 248 (); and 361 (100%); a total of 2,385 out of 2,420 (). Thus the number of eggs per ball ranged 207 to 408. Thus it can be seen that Baeus calif ornicus and its relative B. latrodecti are the most effective parasites of the black widow yet known, and we can hardly expect greater effectiveness within an egg ball than , although we do expect the percentage of parasitized balls to f PLATE 27 Section of egg ball of Latrodectes mactans with empty puparia of Pseudogaurax signata. Enlarged approx. x 7. Photo by Cobb. 102. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Southern California Academy of Sciences. Los Angeles, Calif. : The Academy
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