\u3ci\u3eForficula Auricularia\u3c/i\u3e L. (Dermaptera: Forficulidae) in Michigan

(excerpt) Although Forficula auricularia Linnaeus, the European Earwig, has been known to occur in Ontario, Canada since prior to 1937 (Vickery and Kevan, 1967), invasion of Michigan by this species is of more recent date. A specimen in the University of Michigan Museum of Zoology was taken at Lansing in 1948 and, judging from specimens at hand, the species was fairly common there by 1964. In 1966, Thomas E. Moore, of the Museum of Zoology, took a number of specimens at Beulah in Benzie County and informed me that the earwig was rather abundant on common milkweed. Since that time there appears to have been an explosive build up of populations in the northwestern part of the state. Auricularia is reported as occurring in great numbers around Benzonia, Benzie County and in Charlevoix, Charlevoix County where they have been observed in numbers approaching tens of thousands. I have also seen specimens from Missaukee County, Harbor Springs in Emmet County, Alpena in Alpena County, and Detroit, Wayne County. An undocumented report indicates that the species was observed in 1971 in large numbers at Big Rapids, Mecosta County

Some R.R. Dreisbach Collecting Localities in South-Eastern Texas and Northeastern Mexico

Excerpt: During July and August, 1954 the late Robert R. Dreisbach of Midland, Michigan, devoted several weeks to the collection of insects in Texas and Mexico. Dreisbach was an extremely active and indefatigable person. His collecting efforts were not limited to the accumulation of materials of immediate interest to him, and he assembled large numbers of many species of insects. He maintained a general collection and, from time to time, sent portions of it to various specialists for determination. Numerous new species have been described from this material. In identifying the Orthoptera, I noted several discrepancies in the date-locality data accompanying the specimens. Fortunately. I was able to work out and clarify a number of these inaccuracies with Dreisbach before his death in 1964

Manipulators with flexible links: A simple model and experiments

A simple dynamic model proposed for flexible links is briefly reviewed and experimental control results are presented for different flexible systems. A simple dynamic model is useful for rapid prototyping of manipulators and their control systems, for possible application to manipulator design decisions, and for real time computation as might be applied in model based or feedforward control. Such a model is proposed, with the further advantage that clear physical arguments and explanations can be associated with its simplifying features and with its resulting analytical properties. The model is mathematically equivalent to Rayleigh's method. Taking the example of planar bending, the approach originates in its choice of two amplitude variables, typically chosen as the link end rotations referenced to the chord (or the tangent) motion of the link. This particular choice is key in establishing the advantageous features of the model, and it was used to support the series of experiments reported

\u3ci\u3eSaga Pedo\u3c/i\u3e (Pallas) (Tettigoniidae: Saginae), an Old World Katydid, New to Michigan

At least four species of Old World Tettigoniidae are known to have been introduced into, and to have become established in the United States. One of these, Phaneroptera quadripunctata Brunner was first taken at Niles, California in 1932 and was reported by Strohecker (1952). The other three have been taken during the past two decades. Strohecker (1955) recorded Platycleis tessellata (Charpentier) from a specimen captured at Placemille, California in 1951, Urquart and Beaudry (1953) recorded Metrioptera roeseli (Hagenbach) as occurring at Ville Saint-Laurent and at Montrdal, Qudbec, Canada in 1952, and Gurney (1960) stated that the first specimens of Meconema thalassinum (De Geer) were taken at Little Neck, Long Island in 1959. All four of these species are established and the last three have been extending their ranges. (Kevan, 1961; Rentz, 1963; Johnstone, 1970). M. roeseli has moved the farthest, it is found widely distributed in Qudbec and New York, and is believed to occur in Vermont, Pennsylvania and Eastern Ontario (Vickery, 1965; Vickery and Kevan, 1967)

Diophantine Approximation with Products of Two Primes

We show that for any irrational $\alpha$ and any $\tau<8/23$ there are infinitely many $n$ which are the product of two primes for which $$\|n\alpha\|\leq n^{-\tau}.$$ We also show that for all sufficiently large $b$ there exist 3-digit palindromes in base $b$ with precisely two prime factors.Comment: 25 page